The material of choice for backplates is stainless steel or aluminium. Sometimes is plastic (ABS) used. Stainless steel is used to get additional 3kg of ballast, aluminium or plastic is used if you get too much negative buoyancy with your rigg. If you buy one, make sure the distance between the holes for the thread bolts of your doubles is standard and the notch is deep enough for the wing nuts. You can fix at the backplate a bag which carries – for open water dives – a liftbag.
At the shoulder harness are 3 D-rings to carry backup lights, longhose, lighthead, state bottles and pressure gauge – you won´t need more D-rings. The D-rings itself are kept in place by triglide D-ring fasteners. At the front of the crotch strap is a D-ring for the towcord of the scooter an at the back is a D-ring for additional stuff like reels.
At the abdominal belt is at the left hip a D-ring for the pressure gauge and stage tanks. The buckle is at the right side, because it´s put through the loop ob the crotch strap. Left of the crotch strap is the knife put on the webbing. On the right side is the lightcanister put on the webbing and held in place by a second buckle.
Fitting of the Harness
A few tips for the fitting of the harness should help you to make sure your backplate is in the right positon for your first dive: the shoulder staps need to be a little bit loose to make place for the drysuit and underwear, an on the other side it´s helpful for getting in and out of your rig. A good measure is to get your fist between the webbing and your chest.
The two chest D-rings should be positioned in a manner that you reach them if you move your hand to the chest, when holding your arm out horizontally. This makes clipping D-rings with one hand easy (longhose, lighthead, stages, backuplight). Beside that the D-rings are a little bit bent to ease the clipping. The D-ring on the left hip is so positioned that it is about a handwith from the backplate. This brings stages in a good position to get in the slipstream. It also makes clipping of stages and pressure gauge hasslefree.
The scooter D-ring is placed at the front of the crotch strap. The exact position has to be found by everyone by itself at scootering. It´s good to start slightly below the loop where the abdomial belt is put through. The crotch strap itself has to be snug enough to make sure the rig is tight enough without beeing uncomfortable. If your buddy gets towed with the scooter for example, he has to grab the crotch strap without any problems. If you switch from dry- to wetsuit, it will be necessary to refit your harness.