Spr. Loaded Alum Block on Slider for 3/4" T-Track 303-72

303-72 Stand up spring block for 3/4" T-Track. Delrin(tm) sheave ensures smooth lead and high safe working load. Anodized Aluminum cheeks and Stainless Steel slider provide a strong, reliable block. Spring pin allows easy adjustment. Track Size 3/4" x 1/8" (19 mm x 3 mm), Boat Size Up To LOA, Displ., Sail Area: 20', 2000 lbs., 225 sq. ft. (6 m, 910 kg, 21 m2), Sheave Dia. 1-7/16" (40 mm), Max Line 7/16" (11 mm), L 2-1/2" (64 mm), W 31/32" (25 mm), H 3-17/32" (90 mm), Bearing Height 2-5/32" (55 mm), SWL 1000 lbs. (450 kg), Weight 4.0 oz. (113 g)