Threading Tool, Internal, 1/2" Indexable, SIR0500K11 

This product works with these LittleMachineShop.com products:

•   5442 Insert, 11IRA60 Internal Thread, TiN Coated
•   2688 Screw, Insert Retaining, M2.5
•   5551 Torx Wrench, T-8
•   4843 Torx Wrench, T-8, Wiha