Stackable and sturdy plastic. Expect it to last a long time. The grooves to adjust the backrest are deep enough to prevent accidental slippage. Grey color was a bit lighter than expected and appears a bit beige but works for me. Comfy without a cushion but one could be added as needed. Wheels are hidden and are only in the back where the headrest is. Only thing that could make it better is a cupholder!