This housing is designed as small as possible and has a screw hole mount. The circuit board has mount holes inside for 5mm x 1.5mm screws. The lid has a form fitting double 90 ledge to help with final sealing as does the lens with a brim that encases the square part of the lens. At the bottom of the lid is a 2mm x 6mm rectangular hole which is lined up with the three contacts. A light adhesion silicone caulking is recommended for weather sealing the unit.I used 123D Design to build the model, netfabb to check it, craftware beta to slice it on "high quality" settings and create the gcode and a craftbot with black PLA 220 degree extruder, 60 degree bed temp. with kapton tape on aluminum plate. It takes roughly 25 minutes to create one.