The 16 mm is Harken's smallest block. It is perfect for small synthetic control lines found on high-tech dinghies. The patented bearing system uses stainless steel balls in a captive grooved race and has a 250 lb (113 kg) safe working load - the highest on the market compared to similarly sized blocks.Use for: Dinghy control lines, Spinnaker pole trip lines, Big Boat leech lines, Outhauls, Downhauls, Cunninghams, Traveler controls and Halyards on prams.