i3 Prusa (or whatever) enclosure framing hardware II

These are the NewStyle 40x22.5mm end pieces for 3mm acrylic sheet with 1/2"x1/2"x.055" aluminum angle stock for framing.
Uses only two 4mm screws and has deeper slots for the angle stock, 2.5mm wider.
11/10/2015 - Added a middle support piece for large spans.
I made an enclosure for my i3 Prusa printer (http://www.thingiverse.com/thing:970379), they could be used for any other type of enclosure.