Aluminum cheek block with curved base. Curved stainless steel base fits spar diameters up to 2". Delrin(tm) plain bearing sheave ensures high safe working load and is good for static loads. Sheave Dia. 1-7/16" (37 mm), Max Line 7/16" (11 m), L 3-11/16" (949 mm), W 1" (25 mm), H 3/4" (19 mm), Fasteners (4) #10 RH (5 mm), C/C 3-3/16" (94 mm), SWL 1000 lbs. (450 kg), Weight Stain. 2.2 oz. (62 g), Weight Alum. 2.1 oz. (59 g)