They sell the strut as well to fit it to the Pro-Swing Harness which only comes with one strut, which is ridiculous and a money grab when the Pro-Swing harness is so expensive. I want it for the SDC too.
If no one has one Ive thought of a way to make one. 10mm aluminium pipe from Bunnings at under $3 for a meter, cut pipe to length, drill a couple of holes at each end, feed through some cord so it comes out the top and then goes back down to the bottom to leave a small loop at the top, leave a big loop at the bottom for the bungee to hook to, hook a carabiner through the loop each end at the top, and tie off the cord at the bottom. Bingo, job done. The idea of the crossbar is to stop your harness or backpack shoulder straps from pulling in under load of the detector weight and causing the shoulder straps to rub on your neck. The crossbar is effectively a spreader bar. I discovered this when I thought Id use a piece of cord between the shoulder straps but the weight of the detector pulled the straps against my neck. Whilst not a huge deal I think it would get annoying after hours of detecting.
