Harken 75mm Carbo Double Block with Swivel Head and Becket Sale_20plus which protects the neoprene upper

which protects the neoprene upper from lateral abrasion and gives you grip on the parts of the deck where the sole itself doesn't reach

free from dirt

*Depends on the type of rope in use with the sheave

Sheave 57 mm Length  142 mm Weight  264 g Shackle Pin  6 mm Maximum Line  10 mm  Maximum Working Load  1080 kg Breaking Load  2270 kg

If you're after a more performance-focused boot for ILCA racing or foiling

Harken 75mm Carbo Double Block with Swivel Head and Becket Sale_20plus which protects the neoprene upperLow friction Carbo Air blocks are lightweight, strong, reliableand affordable. Companions to the popular Harken Black Magic block line, these small, compact blocks have very high working loads for safe, easy trimming. Sheave 75 mm Length 178 mm Weight 419 g Shackle Pin 8 mm Maximum Line 14 mm Maximum Working Load 1100 kg Breaking Load 2722 kg