5/16" x 1 3/4" BSW Bolt Hex BS193:1929 in EN1A mild steel. Thicker hex head than modern fasterners but with the same width.Full bearing, single chamfer.TPI: 185/16" x 1 3/4" BSW Bolt Hex BS193:1929£2.78PriceFinish*SelectDiameter*SelectLength*SelectQuantity*Add to CartDeliveryDelivery costs are based on the weight of your order UK Delivery: 3 to 5 business days International: 5 to 7 business days