This is a plastic shackle used to secure a slug or slide to a sail. It features the strongest screw design closure that permits easy detachment and re-attachment (screw is included). The pip prevents the shackle from jamming and keeps the sail slug or slide from abrading the boltrope.
Sail shackles are popular due to their quick installation time. This shackle must be used with a pressed #1 or #2 spur grommet in the edge of the sail. Plastic or nylon shackles do not need a plastic insert to protect the sail.