
HARKEN 40MM Twing Block
40mm Twing Block
Low-friction Carbo Air blocks are lightweight, strong, reliable—and affordable. Companions to our popular Harken Big Boat blocks, these small, compact blocks have very high working loads for safe, easy trimming.
Features:
- Opening side plate - Easy to rig and remove from sheet
- Spring biased to open when unlatched - One-handed operation
- Roller at pivot base - Use 1:1 or 2:1 up-down control
- Carbo Air® block construction - High strength for durability and lightweight for maximum float in light air
Uses:
- Dinghies, sport boats, and small keelboats
- Spinnaker sheet and guy control
- Code zero sheet up-down control
Specifications:
- Sheave Ø (mm): 40 mm
- Sheave Ø (in): 1-9/16 in
- Length (mm): 89 mm
- Length (in): 3-1/2 in
- Weight (g): 86 g
- Weight (oz): 3 oz
- Maximum line Ø (mm): 12 mm
- Maximum line Ø (in): 3/8 in
- Maximum working load (kg): 275 kg
- Maximum working load (lb): 606 lb
- Breaking load (kg): 825 kg
- Breaking load (lb): 1818 lb
In Stock: Ships Within 2-4 Business Days
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Essential equipment for projects and home repairs, plus specialized climbing and outdoor gear—selected for lasting quality. Order with confidence: we stand behind every item and provide a reliable, U.S.-based ordering and shipping experience.
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