This is an easy fix to a common charging system issue found on Harley Big Twin Shovelhead & Evolution engines. This retainer simply holds the regulator/rectifier plug tight against the stator plug preventing arcing, which leads to frequent premature failure. The retainer mounts through the front left engine mount bolt (reusing the factory hardware.) Made from 18-Gauge 304 Stainless Steel so it won't rust and eventually fail over time even after being exposed to the elements and engine vibrations. Fits 1970-1999 Harley Big Twin FX/FL Models, Touring, Softail, Dyna & FXR Models with Shovelhead & EVO/Evolution Engines equipped with a Regulator Rectifier that has a Right Angle Plug. Does NOT fit Twin Cam Engines.