3U Rack Space 12-Inch Depth Drawer for Server Rack for Rack Mount Drawer Server Cabinet Case

Rack Unit(U) Guide:  1 Unit = 1. 3/4H

The ProX T-3RD-12 3U Rack Drawer is a handy, small storage unit. Fits all USA popular standard 19 inch wide rack mounts.  Heavy Duty all-metal construction.

The ProX 19 wide Rackmount Drawer, 16-1/8 useable width, transforms any standard rack case with a convenient, secure storage unit that can hold a wide variety of pro DJ and audio equipment: accessories, adapters, cables, iPods, etc...
https://www.proxdirect.com/products/view/740