allows 6:1 and 4:1 rigging options.Great for mainsheet or spinnaker blocks and control lines on offshore yachts. Robust construction handles high loads. Ball-bearing sheaves minimize friction. Beefier posts and wrap-around straps create much higher working loads. Three-way head system permits blocks to swivel or be fixed side-to-side or fore-and-aft. Beckets are removable. Where applicable, blocks use 1/4" fasteners.Key FeaturesGreat for mainsheet or spinnaker; control lines on offshore yachtsTough construction handles high loadsHigh-load Torlon ball-bearing sheaves minimize friction3-way head system for swivel or fixed mountingWrap-around stainless straps; stainless-steel shackleSheave Diameter: 3" (76 mm)Max. Line Diameter: 9/16" (14 mm)Max. Working Load (MWL): 1800 lb. (816 kg)Breaking Load: 5000 lb. (2268 kg) Weight: 18 oz (510 g)Length: 9 1/2" (241 mm)