Alvin and Co. CK38 These convenient height extension kits convert Alvin office-height chairs into drafting-height models. Each kit includes a strong cylindrical steel shaft with tapered end that locks into the chair base. Foot rings can be adjusted vertically and then locked at the desired height. It is recommended that extension kits be attached when the chair is first assembled. Features: -Product Type: Foot Rings.-Finish: Black and chrome.-Hardware Finish: Chrome.-Distressed: No.-Material: Metal -Material Details: Stainless steel..-Hardware Material: Stainless steel.-Solid Wood Construction: No.-Number of Items Included: 3.-Pieces Included: 1 Footring adjustment knob, 1 footring, 1 extension tube.-Water Resistant: No -Water Resistant Details: ..-Scratch Resistant: No.-Non-Skid: No.-Upholstered: No -Upholstery Material: .-Upholstery Color: .-Tufted: .-Cushion or Upholstery Fill Material: .-Foam Density in Pounds per Cubic Foot: ..-Lumbar Support: No -Passive or Active: ..-Arms Included: No -Arm Type: ..-Padded: .-Heated Feature: No.-Portable: No.-Locking Capability: Yes.-Adjustable: Yes -Adjustable Strap: No..-Compatibility: Fits Alvin chair models CH112, CH222, CH277, CH290, CH300, CH444, CH555, CH728, and CH777.-Swatch Available: No.-Recycled Content: No -Total Recycled Content (Percentage): .-Post-Consumer Content (Percentage): .-Remanufactured/Refurbished: ..-Product Care: It is recommended that extension kits be attached when the chair is first assembled. Use as foot rest only, do not stand on it..Dimensions: -Overall Height - Top to Bottom: 7.5.-Overall Width - Side to Side: 18.-Overall Depth - Front to Back: 18.-Arms: No -Arm Height - Top to Bottom: .-Arm Width - Side to Side: .-Arm Depth - Front to Back: ..-Overall Product Weight: 6.Assembly: -Assembly Required: Yes.-Tools Needed: No tools necessary.-Additional Parts Required: No -Parts Needed: ..