It's a case for a 230V/10A-Powerswitch, to feed my 24V-hypercube-evolution-powersupply. You can mount it on a 30x30-aluprofile with two M5-screws and M5-hammernuts. The backplate is made to snap into the case. The powerswitch itself is mountet with two M3-screws and nuts.

Update V2: Increased case-depth by 5 mm. Increased cable-hole-width. Modified stability of case-cover.