It is mainly applicable to the excavation of hard materials. Chuck adapters can maintain good edge sharpness during high-speed use to improve productivity and extend equipment. The chuck clamp router adapter has special sharpening technology, low resistance, high hardness and sharper opening. The chuck has carbide edges, which will give you fast, smooth rotation and efficient operation. It is portable, it has high precision, can achieve tight and stable clamping, and improve work efficiency. The chuck adapter can maintain good edge sharpness during high-speed use, so as to improve production efficiency and life. This chuck chuck router adapter has special sharpening technology, small resistance, high hardness and sharp opening. Features Router collet color: black - material: high-speed steel - size: 6/6.35/8 mm/0.24/0.25/0.31 inch. Note: 1. 1 inch=2.54cm/1cm0.393 inch. Please allow 1-3 cm error due to manual measurement. Please make sure you don't mind. Package includes 3 * router chuck