McMaster 3288A71 Turning Carbide Insert Holder, Multi-Lock, Style MTAN, 3/4" Width × 3/4" Height, Left-Hand

Secure carbide inserts inside these holders for stable turning. They’re also known as indexable insert holders. Select a holder that’s compatible with your insert by matching the insert style and inscribed circle diameter (IC). Right-hand holders move from right to left toward the lathe chuck, left-hand holders move from left to right away from the lathe chuck, and neutral holders can cut in either direction.

M-Code — M-code holders secure inserts with both a top clamp and a pin lock, so they’re often used for interrupted or semi-interrupted cuts to keep inserts stable despite vibration. They’re the most commonly used holders with negative-rake inserts.