BORER STC SA425AL Installation of removable seat back support for aft seat of Piper PA-18 Series airplanes DWG 2270. Model Eligibility: Seaplane and landplane versions of PA-18, PA-18-105, PA-18-125, PA-18A-125, PA-18-135, PA-18A-135, PA-18-150, PA-18A-150.
