Just 1mm Aluminium sheet and some basic bench fitting skills. 
Left to right: power inlet jack, quadratt, pedal IO, 1/4 jack IO, stereo out, headphone out (all Intellijel). The 1/4 IO board is the v2 layout, offering varied uses. I have the first two wired underneath as a mono send/return and the other two are the stereo out. The headphone output is also connected underneath so it output the same signal as the stereo outs when u patched.