5T Harken opening block with loop

The Harken 3300 opening block is an essential piece of equipment on board sailing boats. It allows you to guide or deflect a sheet, as well as make adjustments to a static line. Its opening design makes it easy to temporarily install on your rigging without having to dismantle the entire rope system.

The pivoting side plates make installation quick and easy. The strop is fixed on one side and can be released on the other, allowing the block to be fitted around the rope. A Velcro® fastening strap, permanently attached to one of the side plates, keeps the block securely closed once the plates are aligned. Its wide reflective tab makes it easy to handle, even when wearing gloves.

The block features Harken’s ULC (Ultra Light Composite) technology, ensuring smooth sheave rotation and efficient performance under demanding conditions. The Torlon® ball bearings, fitted with Snap-fit cages, are designed to withstand lateral loads. An integrated spacer prevents the hardcoat anodised, PTFE-treated aluminium side plates from binding.

With its 56 mm sheave, this block accommodates ropes up to 16 mm in diameter.

Technical specifications of the Harken 5T opening block with loop:

• Brand: Harken

• Model: Opening block with loop

• Manufacturer reference: 3300

• Sheave diameter: 56 mm

• Length: 86 mm

• Maximum rope diameter: 16 mm

• Maximum working load: 5,000 kg

• Breaking load: 10,000 kg

• Side plate material: Hardcoat anodised, PTFE-treated aluminium

• Bearings: Torlon® ball bearings with Snap-fit cages

• Technology: ULC composite bearing system

• Closure: Velcro® fastening strap