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OM5-EX - Office Master Ergonomic Self Weighing High Back Executive Chair
All fabrics, arms, and other options shown are examples of available customizations. Fabric shown may not be available on all models — see product options for current selections. Colors are approximate. Arms sold separately.
The Office Master OM5-EX Evolved high-back chair offers all the ergonomic innovation of the OM5 Evolved—now with extended back support for taller users or those who prefer a higher backrest. It features the same self-weighing recline system, dual-adjustable lumbar support, and tool-free removable seat with 2.5" depth adjustment. Blending sleek design with adaptive comfort, the OM5-EX is ideal for executive offices, conference rooms, and all-day task seating.
Features:
Features:
- 24.5" Highback Executive Polyflex
- Body-Activated Motion mechanism
- Polyflex with variable back resistance
- Virtual pause/lock
- Tilt Lock
- Field Replaceable Seat
- 350 lbs. Weight Capacity
- Seat Depth Adjustment
- Lifetime Limited Warranty
| Model/Sku | Office Master OM5-EX |
| Overall Width | 28" |
| Overall Height | 40.5" - 45.5" |
| Back | 18″w x 24.5″h |
| Seat | 19.5″w x 17.5-19.75″d |
| Seat Height | 16-21″ |
| Carton Weight | 67 pounds |
| Warranty | Lifetime limited |
Chair measurements are approximate and are based on switching cylinder heights on otherwise the same chair, with the same base and casters. Arm dimensions are approximate as actual measurements will vary depending on a variety of factors: cushion contour(s), seat upholstery, memory foam, etc.
Downloads / Info
- Assembly: Assembly_Instructions_OM5-Series.pdf
- Certificate: Certificate_OM5-Series.pdf
- Disassembly: Disassembly_Recycling_Instructions_OM5-Series.pdf
- Sales: Sales_Tutorial_OM5-Series.pdf
- General Warranty