Belt tensioner screw. Left. Right. A bolt which attaches the heater core or bracket to it's mounting point. A threaded rod with a drive head (such as hex, 12 point, torx, etc.) on one end used to secure the Air Injection System Line to it's mounting point. A threaded rod with a drive head (such as hex, 12 point, torx, etc.) on one end used to secure the Seat Belt Pretensioner to its mounting surface. tensioner screw. HVAC. Seat Pretensioner. Secondary Air Injection Pump Hose. Tube.