This is the Apeks Backplate Stainless Steel or Aluminum Option Features: Offered in either 304 stainless steel or 6061 anodized aluminum alloy. The stainless steel weighs 4.7 lbs (2.15 kg). The aluminum weighs 1.7lbs (780g). 4 each upper and lower slots accommodate nylon cylinder bands so a single cylinder can be strapped directly to the plate. Having a series of 4 slots provides lateral stability of the cylinder that traditional 2 slot plates cannot. 3 holes at the top of the plate offer a range of height adjustments for the buoyancy cells and the cylinders. In addition, a corresponding lower centre slot allows for lower band bolts that are misaligned. 2 wide crotch strap slot. Upper and lower perimeter holes along either side and holes along the bottom allow for the mounting of accessories. Both offer an electro-plate finish and a laser-etched Apeks logo to enhance the look of the plate. The WTX and WTX-D Series is a selection of harnesses, buoyancy cells and accessories which offer unparalleled versatility due to the modular nature of the whole system. Each component can be configured into a highly technical rig for those trained to push the limits, or scaled down to make a travel friendly set up suitable for any diver. The backbone of any system - this cleverly designed back plate can be used with the Apeks Deluxe One-piece Webbed Harness, or inserted directly into the WTX Harness. It is available both in stainless steel and aluminium. "