Irwin Bolt Fastener Remover Expansion Set 5 piece for removing rounded , rusty or painted bolts. Unique reverse spiral flute design securely grips and removes stubborn nuts and bolts. Can be used with a hand ratchet 3/8 in square drive and has hexagon flats for use with a spanner or adjustable wrench. Universal lobular design for all types of fasteners. Sizes: 5/16in, 10mm, 13mm, 11/16in and 3/4in.