Specifications: Sheave: 29mm / 1-1/8in.
29mm Triple Carbo Air Block w/Swivel Weight: 74g / 2. Companions to the popular Harken Black Magic block line, these small, compact blocks have very high working loads for safe, easy trimming.6oz Shackle pin: 5mm / 3/16in Maximum line: 8mm / 5/16in Maximum working load: 449kg/ 990lb Breaking load: 907kg / 2000lb.