Twin Sheet Lead 25x3MM - Black32-77 Twin Sheet Lead block. The anodized aluminum body is machined from 6061-T6 aluminum and articulates to ensure a proper lead. Anodized aluminum sheave runs on Nomex(TM)/Teflon(TM) bearing for a low-friction high strength sheave. Pin stop makes adjustment simple. Features: Track Size 1" x 1/8" (25 mm x 3 mm) Boat Size Up To LOA 29&'; Disp. 5000 lbs. Sail Area 315 sq. ft (8m, 2270 kg, 29 m2) Sheave Dia. 1-1/2" (38 mm) Max Line (2) 1/2" (13 mm) L 3-1/2" (89 mm) W 1-11/32" (34 mm) H 3-9/32" (83 mm) Bearing Height 1-29/32" (49 mm) SWL 2500 lbs. (1135 kg) Weight 10 oz. (284 g)