It might be too late as it sounds like you have already made the purchase, but I made an STA for about $5. I went to the local steel recycler and found a short piece of 4" aluminum channel. Drilled a couple of holes and cut down the sides and ready to go. I actually cut some slots for the cam bands - I have a plasma cutter - but if your wing has the slots then you don't need to. I used the plasma cutter to cut down the sides too but you could use a jig saw or hacksaw even. I don't know if need more weight than an aluminum channel would provide and if you are diving saltwater it might also be a problem.
Hunter
Hunter
