Feature: 1. Suitable for traditional milling machine and comprehensive processing machine 2. Use with 400‑600rpm rotating speed. 3. The mechanical measurement has no clamping error, and the repeated measurement accuracy can within 0.005mm. 4. Specially designed 4mm probe for measuring small aperture and narrow groove. 5. Anti‑magnetic design is adopted for the part of the lower end. Specification: Features: Suitable for traditional milling machine and comprehensive processing machine Use with 400-600rpm rotating speed. The mechanical measurement has no clamping error, and the repeated measurement accuracy can within 0.005mm. Specially designed 4mm probe for measuring small aperture and narrow groove. Anti-magnetic design is adopted for the part of the lower end. Specification: Name: mechanical edge finder Material: carbon steel Size Large end: 20mm / 0.8in Small end:10mm / 0.4in Total length: 90mm / 3.5in Package list: 1 x Mechanical Edge Finder 1 x box Package List: 1 x Mechanical Edge Finder 1 x box