The cheek plate revolves around the sheave axle allowing the block to open; a safety ball stops the block from opening with an adjustable screw to set the ball on locked position. There is a becket for the “hanging line.” Sheave has composite fiber main bearing and double side ball bearings. Hard-anodized and Teflon-coated aluminum cheek plates with yellow rubber side protectors. SH versions include a standard shackle. SN versions include a snap shackle. The blocks can also be attached with line.
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