- Selling point V blue utilizes a unique approach in wire processing that increases cyclic fatigue resistance and improves torque strength. - Due to this proprietary processing, V blue files may appear slightly curved. - While the file can be easily straightened using only your fingers, it is not necessary to straighten the file prior to use. - V blue conforming to natural curvatures. - File Sequence : - 15 04. - 20 04. - 25 04. - 30 04. - 35 04. - 40 04. **For further product information, please contact chat support**