The Notch 1/2" Rigging Block with Ultra Sling is a small sized lightweight arborist block that accepts working lines up to 1/2” (13mm) diameter. Made with 12 strand 5/8" Samson Tenex Tec rope. A rigging block is installed and captured in the terminal eye of the sling. This rigging sling easily adjusts in length using the spliced pockets located at fixed intervals. 6' overall length. The Notch 1/2" Rigging Block is a small sized lightweight arborist block accepts working lines up to 1/2” (13mm) diameter. Hot forged aluminum side plates with rope friendly rounded cheeks. Precision CNC machined aluminum sheaves with wide bend radii. Stainless steel axle. Low profile, secure, easy to-open captive screw pin lock. High wall, full diameter, improved anchor sling protection. Wide, concave upper sheave with a 5/8” anchor sling. Flared side-plates reduce twisting in complex rigging scenarios. Upper sheave diameter: .75 in. (19mm), lower sheave diameter: 1.5 in. (38mm). MBS: 22,480 lbs. (100 kN) Working Load Limit: 4,496 lbs. (20 kN)