Ergonomic Task Chair
HKM-118803 High Back Leather Task Chair
A meticulously engineered seating solution that fuses premium leather craftsmanship with advanced ergonomic science — built for professionals who demand enduring comfort through the longest workdays.
Model: HKM-118803
Why It Matters
Designed around the human spine, built for the modern workspace.
Extended sitting is an unavoidable reality of contemporary professional life. Research from leading occupational health institutes consistently shows that poorly designed seating contributes to cumulative spinal fatigue, reduced circulation, and diminished cognitive focus over time. The HKM-118803 addresses these challenges at the structural level — every contour, every adjustment mechanism, and every material choice has been informed by biomechanical data and user experience testing. The result is a chair that actively supports healthy posture without demanding conscious effort from the user.
High Backrest with Spinal Alignment
The elevated backrest traces the natural S-curve of the spine, providing continuous support from the lumbar region through the thoracic zone. This distributes upper-body weight evenly and discourages slouching even during long sessions.
4D Adjustable Armrests
Move them up/down, forward/back, left/right, and pivot them inward or outward. This four-dimensional freedom lets you fine-tune arm support for typing, reading, or video conferencing — dramatically reducing shoulder and wrist strain.
Signature Feature
4D Armrest Technology: Precision at Your Fingertips.
Most office chairs offer only height adjustment — a one-dimensional solution to a three-dimensional problem. The HKM-118803's 4D armrest system represents a fundamental rethink of how arm support should function. Each armrest operates across four independent axes, allowing you to create a truly personalized support envelope that mirrors your unique body geometry and work style.
Vertical Adjustment
Raise or lower each armrest independently to match your elbow height, ensuring your forearms rest parallel to the desk surface.
Fore-Aft Slide
Slide the armrest pads forward or backward to support your forearms whether you're leaning in for detailed work or reclining to think.
Lateral & Pivot
Shift armrests sideways for broader support, and rotate them to match the natural angle of your arms during different tasks.
Materials & Durability
Premium leather that ages gracefully.
The upholstery is not merely a cosmetic layer — it is a high-performance surface engineered for daily use. Selected for its balance of softness and tensile strength, the leather resists cracking, peeling, and abrasion far longer than bonded alternatives. Its subtle grain texture provides a tactile warmth that synthetic materials cannot replicate, while remaining breathable enough to prevent heat buildup during extended seating.
Genuine Leather Upholstery
Sourced through strict quality protocols, the leather hide offers a refined matte sheen that complements both executive suites and contemporary open-plan offices. It is treated with a protective topcoat that guards against incidental spills and UV-induced fading, preserving its appearance through years of use.
High-Density Foam Cushioning
Beneath the leather sits a multi-layer foam core with a density calibrated to resist permanent compression. Unlike cheaper single-density foams that flatten within months, this layered construction maintains its resilience, providing consistent support from day one through year five and beyond.
The Science of Sitting
Ergonomics that work while you work.
Ergonomics is not about adding lumbar bumps or headrests as afterthoughts — it is a holistic discipline that considers the entire kinetic chain from pelvis to cervical spine. The HKM-118803 integrates several evidence-based design principles into a cohesive whole, encouraging what occupational therapists call "active sitting" — a state where the body is supported yet free to make micro-adjustments throughout the day.
Did You Know?
Studies published in ergonomics journals indicate that users who alternate between upright and slightly reclined postures throughout the day report up to 40% less lower-back discomfort compared to those who remain fixed in a single position. The HKM-118803's responsive tilt mechanism facilitates these healthy posture shifts naturally.
Lumbar Curve Mimicry
The backrest's subtle convexity at the lower region mirrors the natural lordotic curve, filling the gap between the chair and your lower back to prevent the pelvis from rotating posteriorly.
Pressure Distribution
The seat pan's waterfall edge reduces pressure on the underside of the thighs, promoting healthy blood circulation to the lower extremities during prolonged sitting.
Technical Specifications
Every dimension, every tolerance, every detail.
Transparent specifications so you can make an informed decision. All measurements reflect the production standard for the HKM-118803.
Overall Height
46.5 – 50.4 in (118 – 128 cm)
Seat Width
20.1 in (51 cm)
Seat Depth
18.9 in (48 cm)
Seat Height Range
17.7 – 21.7 in (45 – 55 cm)
Backrest Width
19.7 in (50 cm)
Weight Capacity
300 lbs (136 kg)
Net Weight
Approx. 44 lbs (20 kg)
Base Type
5-Star Reinforced Nylon
Workspace Integration
Adapts to your environment, not the other way around.
Whether your office is a dedicated corner suite, a shared coworking hub, or a compact home setup, the HKM-118803's understated design language and neutral palette allow it to integrate without visual friction. The high backrest creates a defined personal zone that signals focus, while the refined leather finish elevates the overall aesthetic of any room.
Executive Office Ready
The chair's commanding silhouette and genuine leather presence make it a natural centerpiece for private offices, boardrooms, and executive suites where first impressions count.
Home Office Optimization
For remote professionals, the chair creates a psychological boundary between work and leisure — an ergonomic anchor that helps you stay productive without sacrificing the comfort of home.
Frequently Asked Questions
Everything you need to know.
What does "4D adjustable armrest" actually mean?
4D refers to four independent axes of adjustment: vertical (up and down to match elbow height), horizontal fore-aft (slide forward or backward to support different forearm positions), lateral (shift left or right for broader or narrower support), and pivot/rotation (angle the pad inward or outward to match the natural orientation of your arms). This level of adjustability is a hallmark of premium ergonomic seating and is particularly beneficial for users who switch between tasks such as typing, using a mouse, writing, and video conferencing throughout the day.
Is the leather genuine or synthetic?
The HKM-118803 features genuine leather upholstery on all primary contact surfaces. Genuine leather is prized for its breathability, natural grain texture, and ability to develop a rich patina over time. It is treated with a protective topcoat that guards against everyday spills and UV exposure. For longevity, we recommend occasional conditioning with a quality leather care product and keeping the chair away from direct heat sources.
What height range is this chair suitable for?
The HKM-118803's seat height adjusts from approximately 17.7 inches (45 cm) to 21.7 inches (55 cm) from the floor. Combined with the high backrest, the chair comfortably accommodates users ranging from roughly 5 ft 2 in (157 cm) to 6 ft 4 in (193 cm). The 4D armrests and responsive tilt mechanism further extend the fit range by allowing fine-tuned customization for different body proportions.
How does the tilt mechanism work?
The chair employs a synchro-tilt mechanism, meaning the backrest and seat pan recline in a synchronized ratio — as you lean back, the seat tilts at a slightly lower rate, keeping your feet grounded and your eyes aligned with your monitor. The tilt tension is adjustable via a knob beneath the seat, allowing you to set the resistance to match your body weight and preferred recline feel. The mechanism can also be locked in an upright position when desired.
Does the chair require assembly?
Yes, some assembly is required. The HKM-118803 ships in a single carton with all necessary hardware and an illustrated step-by-step guide. Typical assembly involves attaching the casters to the base, mounting the gas lift cylinder, securing the seat mechanism, and bolting on the backrest and armrests. Most users complete the process in 20–30 minutes with no specialty tools needed. A standard Phillips-head screwdriver is the only tool you'll need.
How does this chair compare to mesh-backed alternatives?
Mesh-backed chairs prioritize airflow and are often lighter in weight, making them popular in warmer climates. The HKM-118803's leather-and-foam construction offers distinct advantages: superior acoustic dampening (less creaking), a more anchored and substantial feel, and a warmer tactile experience during cooler months. The high-density foam also provides more consistent pressure distribution across the full contact area compared to tensioned mesh, which can create pressure points at the frame edges for some users.
Purchase With Confidence
Your satisfaction, our commitment.
Free Shipping
Complimentary shipping on all orders with no minimum purchase required. Delivered safely to your doorstep.
180-Day Purchase Protection
Extended coverage against manufacturing defects for a full six months beyond your purchase date.
30-Day Money-Back Guarantee
Not completely satisfied? Return the chair within 30 days for a full refund — no questions asked.
24-Month Warranty Service
Comprehensive warranty coverage for two full years, including parts and service for any covered defect.
Nationwide Service Network & Support
With over 3,600+ authorized service centers across the United States, we ensure comprehensive after-sales support for your product, giving you complete peace of mind.
We understand that maintenance needs may arise. When you purchase from us, you gain access to our unparalleled service ecosystem designed for maximum convenience and reliability.
1. DIY Repair & Parts Replacement:
For minor repairs or part replacements that can be handled personally, we provide cost-price genuine parts during the warranty period. Each order is accompanied by clear, step-by-step video tutorials to guide you through the self-repair process seamlessly.
2. Professional Servicing:
For issues requiring expert attention, simply contact our support team. We will locate the nearest authorized service center based on your order and location details. You only need to bring your product to the designated center. Once servicing is complete, we will notify you for pickup. All repairs are free during the warranty period; afterward, only cost-based fees apply.
Every product on Hekomart.com is expertly curated from thousands, quality tested, and lifestyle approved. Elevate your everyday.
Express Delivery Priority - Where Speed Meets Satisfaction
At Hekomart.com, we understand the anticipation that comes with every online order. While most platforms rely on standard economy shipping, we prioritize your excitement by strategically selecting premium express carriers to accelerate deliveries. Our intelligent logistics system analyzes real-time data to optimize routes, partnering with globally-recognized couriers like DHL, FedEx, and UPS to ensure 30% faster doorstep arrivals* than industry averages.
Every package receives 24/7 tracking visibility and proactive delivery updates, transforming waiting time into confidence. For time-sensitive purchases, our "Expedited Service Guarantee" offers optional priority handling at no extra cost, because your satisfaction isn't just a goal – it's the core of our delivery DNA.
*Based on internal 2025 data comparing standard shipping durations across major platforms. Delivery times vary by destination and customs procedures.
Credit Card 180 Days Purchase Protection
The 180 Days Purchase Protection protects the buyer if an item purchased has not been shipped or if a shipped item is significantly not as described by the seller. The 180 Days Purchase Protection covers all purchases and payments made through our website. We accept Visa, Master Card, American Express, and Discover Card. If you don't receive the item that you ordered, or it shows up significantly different from its description, you may qualify for Purchase Protection, and we'll reimburse you for the full purchase price plus any original shipping costs, subject to terms and limitations. If you are charged for a transaction that you didn't make, let us know within 60 days, and we've got you covered.
30 Days Money-Back Guarantee
We are confident that our products are of great quality and even better value. However, if upon receiving and inspecting your item you decide that you want to return it, you will have 30 days as of the date of shipment arrival to return it for a refund minus the shipping cost. No restocking charges. Any additional fees associated with a purchase transaction will be deducted from the amount of the refund.
24-Month Extended Warranty Service
If you purchase products from our website, you have 24 months to request repairs or replacement if any products turns out to be faulty or are not as advertised. During the warranty period if any product is found to have a manufacturer defect, we will repair or replace the defective part(s). If a product cannot be repaired or replaced within a reasonable time, you can request a refund or price reduction. We are confident that our products are of great quality and even better value. However, if upon receiving and inspecting your item you decide that you want to return it, you will have 30 days as of the date of shipment arrival to return it for a refund minus the shipping cost.
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