Selden 45mm Automatic Ratchet Block
Ø5 mm Delrin ball bearings and Ø45 mm carbon fibre reinforced polyetherimide sheave.
The sheave automatically changes from free-turning to ratchet when the load increases. The sailor decides when the automatic ratchet kicks in. The switch-over point is set using an allen key to adjust a screw inside the sheave. Fast, simple, precise.