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EC300 Ergonomic Office Chair
High-Back Ergonomic Office Chair with Height Adjustable Backrest, Sliding Seat & 3D Headrest
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Details
- 5-Position Height-Adjustable Backrest – the entire backrest and integrated lumbar support move together through 5 height positions (2.36" adjustment range) for a more personalized torso fit
- Wide-Surface Lumbar & Sacrum Support – integrated into the height‑adjustable backrest, moves with it through 5 positions for consistent lower back alignment
- 5-Position Sliding Seat – 1.97" / 50 mm adjustment range for personalized thigh support
- 55D High-Density Foam Seat Cushion – helps distribute pressure and maintain lasting support
- 3D Adjustable Headrest – adjusts in height, depth, rotation, and pivot for comfortable neck support
- 4-Position Recline Lock – lockable at 90°, 105°, 120°, and 130° for working, reading, relaxing, or resting
- Adjustable Tilt Tension – rotary control allows you to personalize recline resistance
- Stable Construction – Class 4 gas lift, durable alloy base, and 2.36" / 60 mm quiet-roll casters
- Recommended User Range – designed for users approximately 5'4"–6'1" and 90–220 lbs
ProtoArc EC300 High-Back Ergonomic Office Chair combines a 5-position height-adjustable backrest with wide-surface lumbar and sacrum support, a 3D adjustable headrest, and a customizable sliding seat. Four lockable recline positions and a supportive 55D foam cushion provide personalized comfort for long workdays at home or in the office.
Tips: The lumbar and sacrum support is integrated into the backrest and moves with it through five height positions. Adjust the backrest height until the support aligns comfortably with your lower back.
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EC300 Ergonomic Office Chair
Sale price$229.99
Regular price$269.99
Key Features
Lumbar Support
Adjustable Backrest
Sliding Seat
4 Recline Modes
3D Headrest
Foam Cushion
Overview
Why Choose EC300
The EC300 is engineered for taller users who need full back support. Unlike chairs with separate lumbar adjustment, the EC300's entire backrest—including lumbar support—moves together through 5 height positions (2.36" total range), ensuring integrated support across your spine. Designed for users from 5'4" to 6'1" and up to 220 lbs, it pairs this unified backrest with a 5-position sliding seat (1.97" adjustment), a 3D headrest with height, depth, rotation and pivot control, and 2D height-adjustable armrests.
With 4 recline lock positions (90°, 105°, 120°, 130°) and an adjustable tilt tension knob, you can switch from focused work to reading or relaxing. The breathable soft-touch mesh, 55D high-density foam cushion, SGS Class-4 gas lift, and silent 2.36" casters deliver durable, quiet performance for home office and professional workspaces alike.
FAQ
What makes EC300 different from other ergonomic chairs?
Unlike chairs with separate lumbar adjustment, the EC300's entire backrest—including lumbar support—moves together through 5 height positions (2.36" total range). This provides integrated support for taller users (5'4"–6'1") who want full back coverage.
What height and weight range does EC300 support?
The EC300 is designed for users from 5'4" to 6'1" and supports a weight capacity of 90–220 lbs. It is specifically tailored for taller frames who benefit from the full backrest height adjustment.
How does the backrest and lumbar support work?
The entire backrest—including the lumbar area—adjusts up and down through 5 positions with a total range of 2.36". Unlike separate lumbar systems, this keeps the lumbar support properly aligned with the backrest at every height setting.
Can the seat depth be adjusted?
Yes. The EC300 features a 5-position sliding seat with 1.97" (50mm) adjustment, allowing you to match thigh support to your leg length and keep your back fully in contact with the backrest.
What recline options does EC300 offer?
The EC300 locks in 4 positions: 90° (work), 105° (reading), 120° (calls), and 130° (relax). An adjustable tilt tension knob lets you customize the recline resistance to your preference.
What materials and certifications does EC300 have?
It features a soft-touch mesh backrest, 55D high-density foam cushion, SGS Class-4 gas lift, and 2.36" silent casters. The chair is certified to TUV, SGS, BIFMA, and RHOS standards.
USER FIT & DIMENSIONS
ProtoArc EC300 Ergonomic Office Chair
Recommended User Height: 5'4"–6'1"
Recommended User Weight: 90–220 lbs
Seat Depth Adjustment: 1.97" / 50 mm, 5 positions
Backrest Height Adjustment: 5 positions (2.36" adjustment range)
INCLUDED COMPONENTS
EC300 Ergonomic Office Chair, Headrest, Armrests, Seat Cushion, and User Manual
SPECIFICATIONS
Lumbar Support: Wide-surface lumbar and sacrum support integrated into the height-adjustable backrest
Backrest Adjustment: Entire backrest and lumbar support move together through 5 height positions (2.36" adjustment range)
Seat Cushion: 55D high-density foam
Headrest: 3D adjustable for height, depth, rotation, and pivot
Armrests: 2D height-adjustable armrests
Recline Lock Positions: 90° / 105° / 120° / 130°
Tilt Tension: Adjustable rotary knob
Base: Durable alloy base
Gas Lift: Class 4 gas lift
Casters: 2.36" / 60 mm quiet-roll casters
Backrest Material: Soft-touch mesh
Seat Material: 55D high-density foam cushion
Assembly Time: Approximately 20 minutes
USER MANUAL
