Harken 40mm Carbo Air® Stand-up Block with spring to construct a 2:1 or 3:1 purchase. 

Low-friction Carbo AirBlocks® are lightweight, strong, reliable—and economical. Consistently 30% lighter and 60% stronger than equivalent Classic blocks. The sideplates are UV-stabilized, high-strength resin and designed for small-diameter lines favored by racers. Good for jib and mainsheet systems on high-performance dinghies, and for high-load control lines on small keelboats.

Recipient of both the Dame Award and Sail Magazine’s Freeman-Pittman Award for innovation, this innovative line of blocks turns fiber-reinforced composite construction into a reliable strength-to-weight ratio you can depend on. Companions to the popular Harken Black Magic block line, these small, compact blocks work well with very high working loads for easy trimming.

• High strength-to-weight ratio block
• Harken’s most innovative blocks
• 30% lighter, 60% stronger than equivalent conventional blocks
• Smaller block for jib and mainsheet systems on high-performance dinghies
• Use for high-load control lines on small keelboats
• Stainless steel swivel shackle
• Sheave Diameter: 1 9/16" (40 mm)
• Max. Line Diameter: 3/8" (10 mm)
• Max. Working Load (MWL): 485 lb. (220 kg)
• Breaking Load: 1620 lb. (735 kg)
• Weight: 1.7 oz. (48 g)
• Length: 2 3/4" (70 mm)