The swing-side snatch block features a lightweight 4" (100 mm) diameter deep groove aluminum sheave, with stainless steel plates that swing open to install rope. Sintered bronze bushing on stainless steel shaft provides 98% efficiency. Particularly useful for use when doubling the line, the rope cannot accidentally come out of the block. Use the steel locking carabiner to anchor to a polyester sling. Not designed for steel cable.