This is 20 inches deep and fits ATX motherboards.

I installed (a rare) 2u redundant 350w PSU from iStarUSA (IS-350R)

I also have a set of sliding rails I will be sending with this unit, they glide smooth, they just require some wrestling with the server to screw into the chassis.

A standard ATX motherboard will fit into this chassis with a low profile cpu air cooler.

You can ask me more questions, or see the product on their website: https://www.istarusa.com/en/istarusa/products.php?model=D-200SEA

Fast shipping, with the correct sized box + excess use of packing material.