Manufactured from selected steel these boring bars are accurately machined. Bars incorporate broached holes that accept standard high speed steel or carbide toolbits conveniently. Bars are supplied with an allen-key but without toolbits. Boring Bar Length: 9-1/4 inch (235mm) Boring Bar Diameter: 3/4 inch (19mm) Holder Length: 3-3/4 inch (95mm) Square Size: 1 inch (25mm) Tool Bit Size: 5/16 inch