Series 19 Utility Block(TM) - Single - Ferrule Eye HeadStainless steel cheeks and Acetal sheaves ensure a long service life with virtually no maintenance. Hollow rivets in the block heads can be fitted with shackles, which can also be used to add a becket for extra purchase. Features:Lightweight durable constructionEconomicalMaintenance freeApplications:Vang, cunningham and trapeze retriever systems on dinghiesLeech line tackles, bunk adjusters, etc on larger boatsMaterials:U.V. stabilized acetal sheavesGrade 316 Stainless Steel cheeksSpecifications:Sheave : 19mm(3/4)Max. Rope : 5mm(3/16)M.W.L.: 150kg(330lbs)B. L.: 450kg(990lbs)Weight: 10g(0.4oz)