Product Description Harken 41mm Ball-and-Socket Base — SwivelStand-up bases allow a wide variety of blocks to be held upright, swivel freely, or pivot so lines have a fairlead under load. The ball-and-socket design lets blocks articulate up to 45 degrees and swivel freely. The 460 and 461 bases (high-load versions of the 010 and 029) have stainless steel reinforcement plates to handle the high load capacities of 57 mm and 75 mm Carbo blocks.Specifications: Height (in) 2 in Weight (g) 128 g Weight (oz) 4.5 oz Fasteners (mm) 5 FH mm Fasteners (in) #10 FH in Maximum working load (kg) 454 kg Maximum working load (lb) 1000 lb Breaking load (kg) 1134 kg Breaking load (lb) 2500 lb Base Ø (mm) 54 mm Base Ø (in) 2 1/8 in Height (mm) 51 mm Pin Ø (in) 1/4 in Pin Ø (mm) 6 mm Inside socket Ø (in) 7/16 in Inside socket Ø (mm) 12 mm Use with blocks 75 mm Carbo