Fiddle block with anodized aluminum cheeks and snap shackle attachment. Works with 704-75, 704-51 for a 4:1 purchase. Delrin(tm) sheaves feature a single top sheave and two in-line sheaves to spread the load reducing friction and chafe. Swivel snap shackle head design may be locked in place to avoid twist. Upper Sheave Dia. 2 3/8" (60mm), Lower sheaves diameter 1-13/16" (46mm), Sheave Dia. 2 3/8" (60mm), Thickness 1-3/32"(28mm), Width 3 31/32" (101mm), Length 8-1/4" (210mm), SWL 2250 lbs. (1020kg), Weight 15.3oz. (434g), Max Line 1/2" (13mm)