GARMIN GFC500 Avionics Hardware Kit for Cessna 172 A/B/C- 175 A/B/C Per Drawing Number 190-02291-0D. Includes Best Source Hardware For 2 Servo and Pitch Trim Options per Install Manual (340-00234-00, MIL-I-3190/3, MS3340-1-9, MS3367-4-9, S-225-1, S-237, S-329, S330-2, SWP-3/38BK Not Included).