Harken 40mm Double Block — Swivel Father's Day 2023 They form light-duty mounting bases

They form light-duty mounting bases for blocks

Maximum working load (lb)400 lb

Doubles feature composite line guides that are integrated into the block head

Ball bearing swivel bases feature dual rows of Delrin® ball bearings that swivel freely even underhigh loads

Harken 40mm Double Block — Swivel Father's Day 2023 They form light-duty mounting basesPart No. 2638 Sheave (mm)40 mm Sheave (in)1 9 16 in Maximum line (mm)10 mm Maximum line (in)3 8 in Maximum working load (kg)440 kg Maximum working load (lb)970 lb Low 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.