To prevent the line from twisting or binding when used in a cascade or mainsheet system, this block is supplied with a feature to lock the rotation of the swivel shackle. Use an Allen wrench to tighten the set screw to lock the shackle in position. When used as a swivel block, ensure the set screw is not tightened and the swiveling shackle can self-align to find the fairest lead.

Approximate Dimensions:
• Shackle pin diameter: 5/16"
• Sheave Diameter: 2-5/8" & 1-3/4"
• Maximum Line Diameter: 1/2"
• Bearings: Delrin
• Safe working load: 2800 pounds