The Saf-Deflat-Aer Screw-On Tool is used to safely deflate aircraft wheels. The tool includes a silencer to reduce the noise generated by the escaping air/nitrogen. There are two models to handle every single aircraft wheel valve in the world. The Model 1 (Part Number 320008A-SO) can cater to the large bore Schrader wheel valve typically found on the larger aircraft such as Boeing B747, B767, B777, B787, Airbus A300, A330, A340, A350 and A380. The Model 2 (Part Number 320008B-SO) can cater tothe standard bore Schrader wheel valve typically found on the smaller jet aircraft such as Boeing B737 Classic, B737NG, B757, Airbus A318/319/320/321, Embraer and Bombardier Regional Jets and all other smaller turboprop and turbojet aircraft. For more information visit www.kestrelengineering.com.