Highland BackplatesHighland Backplates come in a variety of options. Aluminum Backplate Features: 5052 aluminum alloy with black anodized finish Weighs 1. 7 lbs (770 g) All edges are beveled to protect the harness The 3 holes at the top of the plate offer variable height adjustment for air cell and cylinder mounting. In addition, a corresponding lower oval slot allows for lower band bolts that may be misaligned Slots at bottom for use with 1 or 2 crotch strap 3 8