This listing is for a pair of anti-rattle, spring loaded drop catch, ideal for trailers, dropside trucks etc... Heavy duty coil spring tensions the latch to prevent rattles when driving. Threaded bolt on design, with M12 thread. Zinc plated for corrosion protection. Reversible slam boss makes this catch suitable for thin and thick tailboard eyelets. Total length 85mm. Barrel diameter 18.5mm.