12V LED fitting for 25mm Aluminium Box Tube - for 30mm LED arrays.

thingiverse

I utilize 25mm aluminum box tubing for the horizontal bars on my roof racks, designed to seamlessly slide onto them and plug into a cigarette lighter socket. As I've also equipped a secondary battery with one of these systems, I required extra power adaptability. Simple assembly requires just a few parts: one 3x20mm nut and bolt per assembly unit, one LED array module, and some suitable wiring (a 4mm grommet hole size is specified). The LED units can be sourced from Jarcar dealers in Australia as 12v halogen substitutes, featuring built-in polarity correction. Alternatively, numerous suppliers on aliexpress.com offer 30mm versions at a significantly lower price - I discovered some for as little as $0.80 each (albeit with noticeably dimmer output). If any difficulties arise, feel free to leave a comment and I'll be happy to assist; the tolerances have been kept relatively loose in response to feedback about my Swiss army SD card holder design's overly tight clearances.