Harken 40mm block on Vectran line with a safety snap shackle. A must have for the top competitor. Not available in France.
 
Make your own 4:1 mainsheet block-ring combination

We introduced the 38mm Windesign low friction ring. Low friction rings can be used in various applications. The 38mm ring is mainly intended to create a 4:1 mainsheet system. Similar to our existing block combination, the EX1319, you can replace the 29mm Harken block by the 38mm Windesign ring. By changing this block, you create a low friction, less heavy and more durable block combination.

It’s easy to create the block combination as shown below yourself.

What you need to make the 4:1 mainsheet block-ring combination:
EX1314 – Harken 40mm block on Vectran line with a safety snap shackle
EX3003 – Windesign 38mm low friction ring
EX13672 – A bit of 2.2mm Vectran line