Installation of Model 4031-01 Transient Suppression Units on Boeing 737 Classic Airplanes fitted with the Simmonds (B.F. Goodrich) Analog Fuel Quantity Indication System in accordance with Smiths Aerospace Document Number 0181-ED, "Supplemental Type Certificate, Top level Drawing - Gauging Transient Suppression Unit for Boeing 737-100, -200, and -300 Aircraft," Revision C, dated June 13, 2003, or later FAA approved revision. View PDF on drs.faa.gov ↗

The STC PDF is authoritative: installation instructions, ICA requirements and limitations.