Made from forged alloy steel, this 14-piece set is heat treated and tempered, nickel chrome plated and polished. Metric set has 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm. Includes reversible ratchet handle, 5/8" spark plug socket, 1-1/2" and 6" extensions and metal storage box. Lifetime warranty. Weight: 4.25 lbs.