SPECS: Bases - 6061 aluminum, mil-spec hardcoat anodized, matte black; steel setscrew, matte black oxide. MCTAR-08HD - 7⁄8" (2.2cm) long x 13⁄16" (3cm) wide. MCTAR-08HDO - 2" (5cm) long x 1" (2.5cm) wide. Other models - 9⁄16" (1.4cm) long x 13⁄16" (3cm) wide. Swivels/Studs - Steel, black finish. Swivels accept slings up to 11⁄4" (3.2cm) wide.