40mm Carbo Air Double Swivel BlockLow-friction Carbo Air blocks are lightweight, strong, reliable-and affordable. Companions to the popular Harken Black Magic block line, these small, compact blocks have very high working loads for safe, easy trimming. Specifications: Sheave A~ (mm)40 mm; Sheave A~ (in)1 9/16 in; Maximum line A~ (mm)10 mm; Maximum line A~ (in)3/8 in; Maximum working load (kg)440 kg; Maximum working load (lb)970 lb; - cis2:mm5mnJlm -Quick Guide (pdf)