Low-friction Carbo AirBlocks® are lightweight, strong, reliable—and affordable. Companions to the popular Harken® Black Magic® line, these small, compact blocks have very high working loads for safe, easy trimming. Part No. 352 Sheave Ø (mm) 29 mm Sheave Ø (in) 1 1/8 in Length (mm) 52 mm Length (in) 2 1/16 in Weight (g) 26 g Weight (oz) .9 oz Maximum line Ø (mm) 8 mm Maximum line Ø (in) 5/16 in Maximum working load (kg) 150 kg Maximum working load (lb) 330 lb Breaking load (lb) 1000 lb Breaking load (kg) 454 kg