Harken 40mm Carbo Block Single w/Swivel Bracket [2637] Marine Navigation & Instruments | Network Cables & Modules The “SSI” system lets you

The “SSI” system lets you reconfigure your sub at the flip of a switch – something you can't do with ordinary marine subwoofers – so it always fit in your system as it evolves

Accepts F31-2201WHA-C insert

the Radar automatically adjusts settings for echo enhancement to help locate birds

Mounts in a common 1-1/8 in hole

Harken 40mm Carbo Block Single w/Swivel Bracket [2637] Marine Navigation & Instruments | Network Cables & Modules The “SSI” system lets you40mm Carbo Block Single with Swivel & Bracket Low friction Carbo Air blocks are lightweight, strong, reliableand affordable. Companions to the popular Harken Black Magic block line, these small, compact blocks have very high working loads for safe, easy trimming. Features: Sheave (mm): 40 mm Sheave (in): 1 9 16 in Maximum line (mm): 10 mm Maximum line (in): 3 8 in Maximum working load (kg): 220 kg Maximum working load (lb): 485 lb