Single Ball Bearing BlockSingle block with aluminum cheeks and ball bearing sheave. Delrin ball bearing sheave ensures low-friction operation. Swivel head may be locked in place to avoid twist.Specifications:Sheave Diameter 2″ (51mm)Thickness 15/16″ (24mm)Width 2 1/8″ (54mm)Length 4 13/32″ (112mm)SWL 1500 lbs. (680kg)Weight 5oz. (142g)Max Line 7/16″ (11mm)