These TCI Performance heavy-duty trans-brake solenoids are engineered with features like a precision-ground steel shaft with a bronze bushing, a shaft-pinned nut for secure placement, and a unique lip seal to prevent fluid leakage while minimizing mechanical drag. Their high-efficiency, precision-wound coil maximizes the amount of copper in the allowable space for maximum force, and their 2-wire setup ensures that a good, quality ground can be established.