For our quarter rack width (1U high) units which include the Redeye 3D, IBP, IBP JR, Monotor, Pepper, i-VOG and Redcloud the part number is RAKL. These are made for Little Labs and are a high quality aluminum extrusion.
Some units are easier to install the rack kit on than others. See detailed installation procedures under FAQs.
You can also order blank panels for empty spots, the part number is BLP (not shown).