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HKM-3643859 Memory Foam Lumbar Waist Support Cushion for Office Chair and Car Seat Use in Black Dark Gray Pink and Blue
HKM-3643859
Memory Foam, Curved Back
The HKM-3643859 is a lumbar cushion filled with memory foam and cut to a contoured curve, so the thickest part sits against the small of the back. The cover is a soft fabric with a zip down one side, and a woven label sits at the centre of the face. The cushion measures about the width of a chair back, which lets it sit flat against an office chair, a car seat or a sofa. It comes in black, dark gray, pink and blue, and the shape is the same on every color.
Key Features
Six details that shape how the HKM-3643859 is built and how it sits.
Memory Foam Inside
The filling is memory foam, which presses back against the shape it is given rather than springing flat. That is what lets the cushion hold the curve of a lower back through a long sit instead of flattening after an hour.
A Contoured Curve
The cushion is cut with a curve across the face and a waist through the middle, so the thickest part sits where the small of the back needs it. The edges taper away, which keeps the cushion from pressing into the sides.
A Fabric Cover With a Zip
The cover is a soft fabric with a zip down one side, so it can be closed flat against the foam rather than left loose. The fabric is smooth to the touch, which keeps the cushion comfortable against a shirt through a working day.
Fits a Chair or a Car Seat
The cushion is sized to sit against a chair back without hanging over the sides, so it stays in place as the seat is leaned against. The same cushion works on an office chair, a car seat or a sofa.
Four Solid Colors
Black, dark gray, pink and blue are solid tones rather than patterns, so the cushion reads as part of the chair rather than as an accessory. Every color carries the same foam, curve and cover.
A Woven Label at the Centre
A small woven label sits at the centre of the face, which is the only mark on the cover. The rest of the surface is plain, so the cushion does not draw attention away from the room.
Overview
A contoured memory foam cushion under a soft zip cover.
The HKM-3643859 is a lumbar cushion with a memory foam filling and a cover in a soft fabric. The face is cut to a contoured curve with a waist through the middle, so the thickest part of the cushion sits against the small of the back while the edges taper away. A zip runs down one side of the cover, and a small woven label sits at the centre of the face. The cushion is sized to sit flat against a chair back, so it works on an office chair, a car seat or a sofa without hanging over the sides, and it comes in black, dark gray, pink and blue. The shape and the filling are the same on every color.
Full Specifications
What the filling, the cover and the shape are made of.
Filling, Cover And Fit
How the foam, the cover and the curve work together.
The HKM-3643859 is a lumbar cushion with a memory foam filling inside a soft fabric cover. The foam presses back against the shape it is given, so the cushion holds the curve of a lower back rather than flattening after an hour of sitting. The face is cut with a waist through the middle, which puts the thickest part where the small of the back needs it while the edges taper away. A zip runs down one side of the cover, and a small woven label sits at the centre of the face.
What’s in the Box
Everything that arrives with the cushion.
1 x Lumbar Cushion
The memory foam cushion with the cover fitted
1 x Fabric Cover
The soft cover with the zip down one side
1 x Foam Insert
The memory foam core inside the cover
1 x Care Guide
Spot cleaning and care guidance
1 x User Sheet
Fitting advice for a chair or a car seat
1 x Warranty Card
Coverage details for the HKM-3643859
Why Choose the HKM-3643859
Six further reasons the HKM-3643859 stays on the chair.
Holds Its Curve
Memory foam presses back against the shape it is given, so the cushion keeps the curve of a lower back through a long sit rather than going flat. That is the difference between support that lasts a morning and support that lasts an hour.
Sits Where the Back Needs It
The waist cut through the middle puts the thickest part of the cushion against the small of the back, with the edges tapering away. That is the part of the back that a flat cushion leaves unsupported.
One Cushion, Three Seats
The cushion is sized to sit flat against a chair back without hanging over, so it moves from an office chair to a car seat to a sofa. It does not need a strap or a bracket to stay in place.
Cover Wipes and Zips
The soft fabric cover closes on a zip, so it sits flat against the foam and can be spot cleaned when it picks up a mark. The cover keeps the foam off the chair and out of the sun.
Plain Enough for Any Room
The solid colors read as part of the chair rather than as a gadget, and the woven label is the only mark on the face. That makes the cushion easy to leave in place.
Ready Out of the Box
The foam and the cover arrive fitted, so the cushion goes straight onto a chair with nothing to assemble or inflate. It can be moved between seats as often as the work does.
Frequently Asked Questions
Quick answers about the HKM-3643859 waist cushion.
Where should the cushion sit?
Set the cushion against the chair back with the thickest part level with the waist rather than the shoulders, then lean back and check that the curve meets the small of the back. A cushion set too high pushes the shoulders forward instead of supporting the waist. If the chair back reclines, tilt the cushion slightly so the bottom edge sits closer to the seat than the top. A cushion set too high pushes the shoulders forward instead.
Will it fit my chair?
The cushion is sized to sit flat against a chair back without hanging over the sides, so it suits most office chairs, car seats and sofas. Check the width of the chair back against the cushion before ordering if the seat is unusually narrow or wide. Because the cushion does not use a strap, it relies on the chair back to hold it in place. The cushion relies on the chair back to hold it in place.
How do I clean it?
Spot clean the cover with a damp cloth and a little mild soap, then let it air dry away from direct heat. Take the foam insert out through the zip first, because memory foam does not take kindly to being soaked or dried on a radiator. Do not put the cover in a washing machine unless the care guide says it can be washed, since the fabric is cut close to the foam. The insert comes out through the zip before the cover is cleaned.
Does it help with long sitting?
The cushion is shaped to support the lower back through a long sit, and the memory foam holds the curve it is given rather than flattening. That is what makes it useful on a working day at a desk or a long drive. Give the foam a minute to take up the shape each time the cushion is sat against, and shift position now and then rather than staying still for hours. Shift position now and then rather than staying still for hours.
How long does the foam take to settle?
Memory foam is slow to return, so it takes a minute or two to take up the shape of a back each time it is sat against. That slow return is what keeps the cushion from pushing back too hard at once. If the cushion arrives compressed from packing, leave it out flat for a few hours so the foam comes back to its shape. Leave a compressed cushion out flat for a few hours.
Which color should I pick?
The cushion comes in black, dark gray, pink and blue, and every version carries the same foam, curve and cover. The choice is about how it sits against the chair rather than about the support, so pick the one that matches the seat. Dark colors hide marks well over a long working week. The support is the same whichever color is chosen.
Quick Troubleshooting
Common HKM-3643859 points and what to check first.
The cushion slides down the chair
A cushion that creeps down is usually set too low, so lift it until the thickest part is level with the waist and the bottom edge rests on the seat. Check that the chair back is not angled so far forward that the cushion has nothing to lean against. On a smooth chair, a strip of non-slip mat under the cushion keeps it where it is put. A strip of non-slip mat under the cushion holds it in place.
The foam feels hard at first
Memory foam is firm when it is cold and softens as it warms, so a cushion that feels hard on a winter morning will settle once it has been sat against for a few minutes. Leave it out flat for a few hours if it arrives compressed from packing. The same slow return is what makes the foam hold a curve rather than flatten. The slow return is what keeps the foam from pushing back hard.
The cover has a mark
Spot clean the cover with a damp cloth and a little mild soap, and take the foam insert out first through the zip. Let the cover air dry away from direct heat, because a radiator can shrink the fabric. Do not rub hard at a mark, since the fabric is cut close to the foam and a wet patch takes a while to dry through. A wet patch takes a while to dry through the fabric.
The zip will not close
Check that the foam insert is sitting square inside the cover rather than bunched at one corner, because a twisted insert holds the zip open. Work the insert flat with a hand through the open zip before pulling the slider. Never force a stiff zip, because the teeth are fine and a bent tooth will not close again. A bent zip tooth will not close again, so never force it.
The cushion feels too thick
A cushion that presses too hard is usually set too high up the back, where the ribs are, rather than at the waist. Drop it down until the thickest part meets the small of the back and the edges taper toward the sides. On a very upright chair, the cushion can also be turned so the thinner edge sits at the top. On a very upright chair, the thinner edge can sit at the top.
It looks squashed after a while
Memory foam loses height over years of use rather than weeks, so a cushion that has gone flat after a long time is at the end of its working life. Leave it out flat overnight to let the foam recover between long sits, and keep it out of direct sun. The cover can be spot cleaned, but the foam inside is the part that sets how the cushion feels. The foam inside sets how the cushion feels over the years.
Service & Policies
Coverage that keeps working long after the box arrives.
Free Shipping on All Orders
Every order ships free. Handling time: 0-1 business days (Monday to Friday). Transit time: 2-5 business days (Monday to Friday). A tracking number is emailed as soon as the parcel leaves our warehouse.
180 Days Purchase Protection
Your purchase is protected for 180 days from the delivery date against manufacturing defects and damage in transit. If something arrives wrong, we make it right.
30 Days Money Back Guarantee
Not completely satisfied? Request a return within 30 days of delivery for a full refund. We keep the process simple and hassle-free.
24 Months Warranty Service
The product is covered by a 24-month warranty from the delivery date against manufacturing defects. Coverage includes parts and labor; normal-wear items are excluded.
Important Safety Notes
Read these notes before the first use of the HKM-3643859.
The HKM-3643859 is a foam cushion for seating, so set it against the chair back rather than on a floor or a step, and check that it does not hang over the sides of the seat. Keep the cushion away from water and from direct sun, and take the foam insert out through the zip before the cover is spot cleaned. Never put the foam in a washing machine or on a radiator, because heat distorts it and it will not come back to shape. The cushion is a comfort accessory rather than a medical device, so speak to a health professional if back trouble continues, and check that the seat is still stable with the cushion in place before it is used.
HKM-3643859 - memory foam lumbar waist support cushion with a contoured curve, a soft fabric cover that closes on a zip down one side and a woven label at the centre of the face. Sold in black, dark gray, pink and blue, sized to sit flat against an office chair, a car seat or a sofa. Read the manual before first use. Nothing here is safety certification advice.
Every product we offer includes a 180-day purchase protection plan at no additional cost. This coverage extends beyond a standard warranty, reflecting our confidence in product quality and our ongoing commitment to your satisfaction.
The protection plan is designed to provide practical help in real-world situations. Whether you encounter a manufacturing issue, a performance problem, or an unexpected accident, our team is ready to assist with clear, fair solutions.
What Is Covered
Manufacturing Defects
We replace items with material or workmanship flaws at no charge.
Performance Failures
Free repair or replacement if the product fails under normal use.
Accidental Damage
One-time courtesy replacement at a reduced price.
Zero Hidden Fees
All shipping costs for replacements and returns are covered.
How to File a Claim
How This Differs from the Warranty
The 180-day purchase protection includes accidental damage and performance failures that are typically not covered by a standard warranty. It provides an additional layer of support during the first six months after purchase, giving you greater confidence and peace of mind.
We want you to be completely satisfied with your purchase. If for any reason you are not fully happy, you may return your item within 30 days of delivery for a full refund. No lengthy forms, no unnecessary questions.
Our return policy is built on a simple principle: if the product is not right for you, we will make it right. We understand that online shopping involves trust, and we work hard to earn that trust with every order.
Return Eligibility
30-Day Window
Request a return within 30 days of delivery.
Original Condition
Unworn or unused, with tags and original packaging.
Proof of Purchase
A receipt or order number is required.
Fast Refund
Refund processed within 10 business days.
How to Start a Return
Returns & Exchanges Overview
Damages & Exchanges
Please inspect your order as soon as it arrives. If the item is defective, damaged, or incorrect, contact us immediately so we can evaluate the issue and make it right. For exchanges, the fastest option is to return the original item and place a new order for the replacement.
We believe in the quality of our products, and we want you to share that confidence. Every product is backed by a 24-month warranty covering all structural and functional components, including zippers, buckles, straps, and fabric integrity.
The warranty is designed to be simple and accessible. You only need your proof of purchase to begin a claim, and our team will assess the issue promptly. If a manufacturing issue arises, we will make it right.
What the Warranty Covers
Comprehensive Coverage
Every part warranted for two full years.
Free Repair or Replacement
Whichever is faster, at no cost to you.
Quick Turnaround
Claims assessed within 1 business day.
Transferable
Warranty follows the product, not the owner.
How to File a Warranty Claim
Every order ships free—no minimums, no hidden fees. We currently deliver across the United States and are actively working to expand to more countries. We partner with reliable U.S. courier services to ensure your order arrives safely and on time.
Our delivery process is designed for transparency. From the moment you place your order to the moment it reaches your door, you receive clear updates at every stage. We carefully inspect each product before dispatch, and we provide tracking information as soon as your order ships.
Our U.S. Shipping Partners
USPS
Official national carrier with nationwide coverage.
UPS
Fast and reliable ground and express shipping.
FedEx
Express delivery with real-time tracking.
DHL eCommerce
Efficient parcel delivery for e-commerce shipments.
Delivery Process
Delivery Time Summary
Cancellations & Taxes
You may cancel your order at any time before it ships. All product prices include applicable taxes, and there are no additional VAT or customs fees for orders delivered within the United States.
Whether you have a question, need help with an order, or just want some advice, our support team is available around the clock. We don't just respond to messages—we work with you to find real solutions that fit your needs.
Our support specialists are trained to handle a wide range of requests, from product recommendations to technical troubleshooting. No matter the question, you can expect a professional and friendly response.
How We Can Help
Product Guidance
Our experts help you choose the right product.
Order Assistance
Modify orders, track shipments, or speed up delivery.
Warranty & Returns
Start claims or returns quickly and easily.
Technical Troubleshooting
Step-by-step solutions for product issues.
Contact Information
24/7 Phone
+1 (209) 280-3200
support@hekomart.com
Address
3401 Dale Rd, Modesto, CA 95356
Support Hours
Available 24 hours a day, 7 days a week
