Engineered Now The Original Headrest for The Herman Miller Aeron Chair (H4 for Classic, Carbon). Special Feature: Adjustable Headrest. Size: H4 for Classic. Age Range (Description): Adult. Use for: Head, Neck. Number of Pieces: 1. Item Weight: 3.5 Pounds. UPC: 783583934800 783583934831 783583934794. Product Dimensions: 12″L x 6″W. Unit Count: 1.0 Count. Item Weight: 3.5 pounds. Country of Origin: Taiwan. Item model number: Headrest by Engineered Now. Maximum recommended load: 300 Pounds. Form Factor: Mesh with Frame. Included Components: Headrest, Hex tool, Replacement Bolt for A-Size Chairs, Spare Caps, Instructions. And we will work with you to resolve it to your satisfaction.