A2052 - 50MM DYNAMIC: DOUBLE FIXED/SWIVEL SHACKLE HEADPart # = A2052 Description = Plain Length (mm) = 100 Line Dia (mm) = 5 10 Shackle Pin (mm) = 4mm Breaking Loag (kg) = 950 Max Dynamic Load (kg) = 450 Weight (g) = 144 The A2052 is a high performing ball bearing block, designed to eliminate friction and allow rope to run at great speeds. Ideal for use on Keelboats and Catamarans for a range of applications from jib sheet to mainsheet systems, to backstay tensioning systems and everything in between.