- For isthmus preparation, slender neck for better visibility, shaft 205 total length 31 mm - Application: root canal preparation - H1SML Easy-to-cut endobore for isthmus preparation as part of root canal treatment - The H1SML has a particularly easy-to-cut working part and a long neck for good visibility. Deeper cavity areas in the tooth crown in the pulp area are therefore optimally visible. **For further product information , please contact Chat support**