Aluminum backplates are the most popular with freshwater divers and divers using steel tanks. The 6061 grade aluminum has a durable anodized black finish and is available in a 3 mm version that weighs† approximately { 1.5 lb | 0.66 kg }. For comfort it is compatible with Mares XR Padding Kit.

The Mares XR backplate features a modern laser cut design:

• { 11 in | 28 cm } centers mounting with three holes for height adjustability and a lozenge slot that allows easy assembly on doubles bolts without alignment concerns.
• { 2 in | 5.1 cm } slots to accept directly threaded tank cam bands for single cylinder diving, improving stability by making the use of a single tank adapter optional.
• { 2 in | 5.1 cm } horizontal and angled strap slots to allow your choice of straight or cross-over shoulder strap mounting.
• { 2 in | 5.1 cm } slot at the base to accommodate a crotch strap.
• { 3/8 in | 1 cm } perimeter holes (four on each side and four at the base) for mounting accessories such as light canisters, butt plates, inflation bottles, lumbar pads, and surface marking buoys.
• Rounded corners and all edges are deburred to reduce wear on the harness and wing. The lower corners have a slight bend for comfort.
• { 15.75 in | 40.0 cm } high and { 10.63 in | 27.0 cm } wide at the base, { 8.75 in | 22.2 cm } wide at the top before the corner curve, with "V" depth of { 1.6 in | 4.1 cm }.
• 6061 marine grade anodized aluminum with a flat black finish and silk-screened logo.
• 3 mm version weighs† approximately { 1.5 lb | 0.66 kg }.
• Compatible with the Mares XR Padding Kit.

† Although Mares documentation officially lists the weights as 3mm = 0.75 kg, our own measurements listed above disagree when taken using multiple electronic scales and averaging across multiple items without including packaging.