Harken Apex Limb-O Rigging Block
The Harken Apex Limb-O arborist block is engineered for high-load rigging applications with dynamic impact forces, delivering exceptional strength, control, and durability in demanding tree care environments.
Built with a best-in-class strength-to-weight ratio, the Limb-O from Harken provides enhanced friction, efficient load management, and safe lowering performance, even in aggressive negative rigging scenarios.
Harken Limb-O Rigging Block User Manual (PDF)
- Handles High Impact Loads Designed for rigging scenarios where shock loading and dynamic forces are critical factors.
- Enhanced Friction for Controlled Lowering Improves load control and reduces unwanted acceleration during lowering operations.
- Mid-Line Attach Capability Pivoting side plate allows fast, simple installation anywhere along the rope.
- Compact, High-Strength Design Aluminum construction delivers durability without unnecessary weight.
- Robust Opening Block Design Built for quick deployment and efficient rigging setup.
- Provides clear locked/unlocked status and reliable engagement.
- Wide Rope Compatibility Supports ropes up to 19 mm (3/4") diameter
Rope Diameter Capacity: Accepts up to 3/4 inch (19mm) rigging ropes
Material: Aluminum
Length: 174.75 mm (6.88 inches)
Width: 102.36 mm (4.03 inches)
Thickness: 69.85 mm (2.75 inches)
Weight: 3.135 lbs (1422 grams)
Working Load Limit (Impact): 35 kN (8,000 lbf)
Hauling WLL: 22 kN (5,000 lbf)
Minimum Breaking Strength (MBS): 222 kN (50,000 lbf)
Carabiner Hole MBS: 25 kN (5,620 lbf)
Standards: ASME B30.26-2015 Compliant



