.......the title is a little missleading as I already know that it's 3/8" But what UNF, UNC, BSP, BA, MFT You know what I mean The reason I'm after finding out is I was on the cusp of ordering a LightForce mag base portable work light £65 ish When I remembered that I have a mag mount up the shed that I don't use so I'm going to cut off the coax & bolt a cheaper 10/20 quid work light on top I just need a bolt that will fit