Ronstan Series 40 BB Orbit Block™ can be used for: Mainsheet systems on spinnaker sheet on dinghies to 5m (16ft) Spinnaker sheets on dinghies, sportsboats and small keel boats to 5m (16ft) Halyard, vang and backstay applications on boats to 8m (26ft) Control line applications on larger yachts It is: Ultra Lightweight Low friction 2-stage Orbital ball bearing system Highest working load in its class Low profile and compact High performance cleating Recessed underside to suit curved mounting surface Low mounting points for maximum strength Sheave Ø 40 mm Max. Rope Ø 9 mm Max. Cable Ø - mm Pin Ø - mm M.W.L. 325 kg B. L. 700 kg Weight 32 g