Box spanners are thinner than a socket & are much longer so that they can be used to loosen or tighten bolts & nuts in narrow recesses meaning that they are often used in plumbing maintenance & automotive repair. These tubular box spanner is made from bright plated steel & able to accommodate a tommy bar. Size range: 8-22 mm. Set of 8. Consisting of 1 each of 8 x 9 mm. x 3.1/4 in. Long (82 mm.). Double ended 10 mm. x 2 in. Long (50 mm.). Single ended 11 mm. x 2 in. Long (50 mm.). Single ended 12 x 13 mm. x 3.1/4 in. Long (82 mm.). Double ended 14 x 15 mm. x 3.1/4 in. Long (82 mm.). Double ended 17 x 19 mm. x 3.1/4 in. Long (82 mm.). Double ended 21 x 22 mm. x 3.1/4 in. Long (82 mm.). Double ended 14 mm. Spark Plug Spanner.