Ronstan Series 40 All Purpose Single Block with Loop Head. All purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing. Exceptionally high working loads. Low maintenance, long service life. Self lubricating sheave. Used for Mainsheet, Halyard & Vang. Also for spinnaker control lines on off-the-beach catamarans, one design classes and sports boats up to 8m (26ft). Made from U.V. stabilised Acetal sheaves. Impact and U.V. resistant, fibre reinforced Nylon cheeks. Grade 316 stainless steel bearing race. Grade 316 stainless steel load strap. Impact and UV resistant, fibre reinforced Nylon cheeks. Dimensions: Sheave ? 40 mm Max. Rope ? 10 mm Pin ? - mm M.W.L. 400 kg B. L. 1000 kg Weight 54 g