The elastic functional material with 4-way stretch offers ultimate flexibility and follows your every move

Heavy duty mast heel plug for the Silver and School Optimist masts

Harken® recommends equipping every system with Carbo lead blocks for safe furling from the cockpit

MaterialsAnodized aluminiumWorking load (kg)800Weight (g)5A (mm)8B (mm)10C (mm)12D diameter (mm)25

400 kg Weight 11 g

Harken 22mm Upright Block 243 Harken CARBO AIR BLOCKS 57 MM The elastic functional material withLow friction Micro blocks are compact and lightweight. They are ideal for sailboards, smaller dinghies, and lightly loaded control lines on boats of all sizes. Sheave (mm) 22 mm Sheave (in) 7 8 in Length (mm) 38 mm Length (in) 1 1 2 in Weight (g) 28 g Weight (oz) 1 oz Maximum line (mm) 6 mm Maximum line (in) 1 4 in Fasteners (mm) 5 RH mm Fasteners (in) #10 RH in Maximum working load (kg) 91 kg Maximum working load (lb) 200 lb Breaking load (kg) 544 kg