Stanchion Block SB4
Clamps on to 1 1/4″ Stanchion without needing to cut lifelines. Line runs on outside of stanchion. One screw adjustment. Has twin sheaves with ball bearings.
This is a picture of an SB-3 on a 25mm stanchion. The SB-4 is just a bit bigger.
Product unit weight grams: 283 (Ounces: 10)