Blocks by Range

Low-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: 22 mm / 7/8 in Length: 51 mm / 2 in Weight: 57 g / 2 oz Maximum line: 6 mm / 1/4 in...

Low-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. Sheave: 29 mm / 1 1/8 in...

Low-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. Sheave: 40 mm / 1 9/16 in...

40mm ball bearing block from Ronstan in fiddle block configuration. This 40mm range features sheaves running on Acetal bearings that provide high performance & low friction. The 2-stage ball bearing system provides consistent performance under the...

The 16 mm is Harken’s® smallest block. It is perfect for small synthetic control lines found on high-tech dinghies. The patented bearing system uses stainless steel balls in a captive grooved race and has a 250 lb (113 kg) maximum working load...

Low-friction Bullet blocks lead control lines aft. They are compact and lightweight, with fast trim and release under high or low loads. A range of styles lets these blocks adapt to almost all control line applications. Sheave: 29 mm / 1 1/8 in Length:...

Designed to work well as a primary lead block on dinghies and catamarans or for control lines on larger yachts, the Ronstan 30 mm ball bearing block range features sheaves running on Acetal ball bearings for high performance and low friction. The 2-stage...

Low-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: 22 mm / 7/8 in Length: 38 mm / 1 1/2 in Weight: 28 g / 1 oz Maximum line: 6 mm / 1/4...

Low-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: 22 mm / 7/8 in Length: 67 mm / 2 5/8 in Weight: 28 g / 1 oz Maximum line: 6 mm / 1/4...