Baer Heli Coil Tap - Wire Thread Insert - Spiral Flute Tap (STI) - Metric - M12 x 1.25Meet the Baer Heli Coil Tap, a precision instrument built for dependable thread repairs and reinforcements. This Spiral Flute Tap (STI) is designed for metric applications, specifically M12 x 1. 25, to deliver clean, accurate internal threads that form a solid foundation for Heli Coil wire thread inserts. When a thread tears or wears, this tap restores the hole to factory like tolerance, enabling reliable fastener pullout resistance and long service