Harken Element 6239 is a 45 mm double swivel block from Harken’s value-engineered aluminium block range. Element blocks use forged aluminium sideplates with hardcoat anodising, a composite bearing sheave with journal bearing and stainless-steel axle and attachment hardware. The double-sheave layout is suited to multi-part tackles carrying two line parts through one moving fitting. This version also includes an integral becket for terminating the standing end of a purchase. Published specifications include up to 12 mm line, a 875 kg maximum working load and a 1750 kg breaking load. Select the fitting by line size, attachment style and working load, and install fixed versions to suitable supporting structure.