Harken 2143 57mm Carbo Air Flip-Flop Block with Cam Cleat

The Harken 2143 57mm Carbo Air® Flip-Flop Block with Cam is a high-performance small boat sailing block designed to keep lines running low and clean along the deck. Flip-Flop blocks pivot around the line axis to minimize clutter and maintain efficient line management, while the integrated cam cleat allows for quick, secure line locking and easy release.

Part of Harken's award-winning Carbo Air® block family, the 2143 combines lightweight high-strength resin construction with free-running ball bearings for low-friction performance under load. The 57mm sheave diameter handles lines up to 3/8 in. (10mm), making it well-suited for main and jib sheets, spinnaker halyards, and other control lines on small keelboats and performance dinghies.

Key Features:

• Flip-Flop design pivots around the line axis to keep lines close to the deck
• Hinged construction accommodates various lead angles
• Reversible cam arms adjust and lock in a range of positions for crew accessibility and changing lead angles
• Carbo Air® construction — lightweight, high-strength resin sideplates reinforced with densely packed glass fibers
• Free-running ball bearings roll on curved races for low friction and high load efficiency
• 57mm (2-1/4 in.) sheave diameter with maximum line diameter of 10mm (3/8 in.)
• Maximum working load: 300 lb (136 kg)
• Recipient of the Dame Award and Sail Magazine's Freeman-Pittman Award for innovation

The Harken 2143 is an ideal upgrade for small boat sailors seeking a reliable, low-profile deck block solution that combines cam-cleat convenience with the proven performance of the Carbo Air® platform.