Series 40 All Purpose Block - Single CheekFeatures: Exceptionally high working loads; Low maintenance, long service life; Self-lubricating sheave; 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.Can be mounted on masts and booms using the curved surface adapter. Can be stacked to create a double version, but no more than 60% of the rated working load should be applied to the upper sheave. Stackable with Ronstan Series 40 deck organizers.Applications: Mainsheet; Halyard; Vang; Spinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft); Materials: U.V. stabilised Acetal sheaves; Impact and U.V. resistant, fiber reinforced Nylon cheeks; Grade 316 stainless steel bearing race; Alloy cheek plates; - cis2:mm5mnJlm -