This safety valve fits Mack air brake systems and is also used across Volvo and Navistar platforms, built as a replacement for the original equipment part. It opens automatically once pressure exceeds a preset threshold, releasing excess air from the circuit to protect the system from damage. Sold individually as a single unit.Interchanges:10AC13065Navistar 13943HMack 20QE112920QE81001Volvo 72802-0002745-284142LSV-3615FeaturesAir brake safety valveSold pack of 1 eachSold by Pro Gear and TransmissionTech SpecsSell pack: 1 EACH