Features: This is a set of 10 pieces sturdy tools to help remove nuts, bolts, screw heads, studs, etc. Suitable size: The damaged nut bolt extractor fits heads sized 9, 10, 11, 12, 13, 14, 15, 16, 17 and 19mm. Positive grip: Spiral cut teeth provide a positive grip to remove rounded or damaged bolts. Strong and durable: made of Carbide, they are of strong strength and long durability. Easy storage and transportation: These tools can be with a metric spanner or socket for fast work. All these tools are packed in a case for easy storage and transportation. describe: Name: Screw Remover Kit Material: cemented carbide Model: high model Specification: 9, 10, 11, 12, 13, 14, 15, 16, 17, 19mm Material: Carbide colour: As shown Package Contents: 1 x screw remover set (10 x screw remover, 1 x aluminum box) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.