This is a 10 piece heavy duty tool set for removing nuts, bolts, screw heads, studs, etc. It fits 9, 10, 11, 12, 13, 14, 15, 16, 17 and 19mm heads Spiral cut teeth provide a positive grip for removing rounded or damaged bolts Made of hard alloy, they are of high strength and long durability These tools can be driven with a metric wrench or socket for quick work Features: Material: alloy The color black Fit head size: 9mm/0.35, 10mm/0.39, 11mm/0.43, 12mm/0.47, 13mm/0, 51, 14mm/0.55, 15mm/0.59, 16mm/0.63, 17mm/0.67, 19mm/0.74 Case Size: Approx. 17.2 x 7.9 x 3.5cm / 6.77 x 3.11 x 1.37 Package weight: approx. 368g Package included: 1 x 10pcs/nut remover kit The size within 1-3cm size difference is within the normal range due to manual measurement. Color may have a little difference due to lights, screens.