Sheave Diameter		Cable Diameter		Weight		Maximum Working Load		Breaking Load
in	mm	in	mm	lb	kg	lb	kg	lb	kg
20	508	3/8	10	42.5	19.3	10000	4535	20000	9091

Maximum working loads are 4:1 coefficient ratio of the breaking load. Human suspension applications require 10:1 ratio.
WARNINGS AND INSTRUCTIONS. You must carefully read, understand, and follow all of the warnings and instructions in the User Manual provided by Harken in order to avoid an accident. Never, under any circumstances, exceed the maximum rated load.

Delrin® roller bearings are housed in a center cage to keep them parallel for low-friction efficiency. Captive Torlon® ball bearings handle side loads.

The pulley's large center hole moves the center of gravity toward the shackle, improving the pulley's ability to align with the cable under tow.

The pulley's wide throat allows passage of wire terminals.

Pulleys accommodate line counter instrumentation.

UV-stabilized 6061 aluminum sideplates are deep-saturation, Hardkote-anodized for maximum protection; Teflon-impregnated for a smooth, slippery surface.

The use of Helicoils® and isolating materials between aluminum and stainless steel components minimizes corrosion.

The sheave's durable, lightweight Nylatron® material has high mechanical strength and stiffness, resists static electricity, and has excellent wear resistance.

The sheave's wide diameter and Nylatron's® exceptional self-lubricating and wear characteristics deliver cable without damage.

Flushing with fresh water after each use will keep the self-lubricating bearings free rolling.

One Allen wrench is the only tool needed to disassemble the block.

All bearings are captive so there is no worry about losing parts.