Note this part has now been added directly to base model Size A Helmet - consider this thing deprecated.
This is a LED mount for the rear insert in this full size A Halo Helmet.
This insert takes two 5mm Leds into the bottom of the piece.
The body is deeper to take the leds and diffuse the light slightly.
All designed in Autodesk Fusion 360
All printed on a Makerbot Replicator 2.
Standard profile, 2 shells, 10% infill.