This Harken Zircon 57 mm single block is an ultra-free-running sailing block developed for trim and sheet systems where low friction is critical.
The block is equipped with ceramic ball bearings, which provide extremely smooth running and make it particularly suitable for sailing in very light air.
With a maximum line diameter of 10 mm, a working load of 150 kg, and a breaking strength of 450 kg, it is a precise choice for demanding sailors who want efficient power transfer and responsive trim.
Key features
57 mm single block for sailing
Ceramic ball bearings for very low friction
Suitable for light air sailing
Maximum line Ø10 mm
Maximum working load 150 kg
