Goxawee Keyless chuck is made by superior material, which can hold the bit shank from 1/8 inch to 1/64 inch steady. It is suitable for most Goxawee brand rotary tool, like model G4007, G4115, etc. If you need to apply to rotary tool from other brand, check the specification before use, it may not match. For your safety, please make sure the bit is hold in central and align to the chuck port.