Arlington Industries has released the 8161CB non-metallic corner-mount box.

The 8161CB non-metallic corner-mount box.
The 8161CB is designed for mounting a security camera, detector or fixture face down on an outside corner, and holds up to 50 lbs.
•For power or low voltage cameras (etc) with mounting holes wider than 4.5-inch apart
•Integral corner-mount bracket
•Non-metallic, UV rated for long outdoor life
•For interior or exterior use in dry, damp or wet locations
Also available with Ground Clip for Canada orders.