Schaefer Clear Step Furling Block Kit
300-76 Clear Step block kit. Includes (1) 300-35 spring clamp on block and (3) 506-44 clear step blocks. Delrin(tm) ball bearing sheaves ensure low-friction throughout the system for easy furling and reefing. Maximum line size 1/2"(12mm), Safe Working load 750 lbs (340g)