To avoid the scuba tank hitting the back of your head, Solution Scuba suggest that you use a crotch strap. In addition, lower the scuba tank on the back by setting the cam straps at the top shoulder of the scuba tank.

It is not necessary to use a hard backplate when you are scuba diving double tanks. Using Dive RiteBC2084 TransPac stabilizing plates would do the trick as well.

Note: The Dive Rite TransPac is not meant to be worn with a metal/stell backplate. When the Dive Rite TransPac first introduced on the diving market in 1995, cold water divers wanted the fit of the Dive Rite TransPac with the added weight of a metal/steel plate. They would put the metal/steel backplate in between the Dive Rite TransPac and the wing to give the dive equipment more weight to counterbalance thick undergarments. Dive Rite developed the TransPlate in response to this need. The TransPlate gives the same comfort and support as the Dive Rite TransPac, yet allows scuba divers to use the harness with a metal or steel backplate.