Screw-in tool for HeliCoil plus thread inserts. High-strength, free-running HeliCoil plus thread inserts made of stainless steel with high wear resistance, low thread friction in tight tolerances, high surface quality, as well as corrosion and heat resistance. The flexible design allows for uniform load and stress distribution, resulting in durable screw connections of the highest quality for all operating loads (static, dynamic) with ideal force transmission. Simple and quick assembly creates a gauge-holding, double-sided usable internal thread.