This air brake hose set fits Mack applications and is built as a matched pair, pairing two distinct air hoses that route air between components to maintain sealed connections throughout the system. The set is packaged as a single sell unit with one of each hose included. It replaces the OEM hoses as a complete kit rather than as individual components.Interchanges:Mack 6635-73151612FeaturesAir hose set, sold as 1 eachIncludes MAC-4171 air hose (Mack 42QE2116P1), qty 1Includes MAC-4170 air hose (Mack 42QE2116P2), qty 1Air brake partTech SpecsSell pack: 1 EACHKit contents: MAC-4171 (Mack 42QE2116P1) air hose, MAC-4170 (Mack 42QE2116P2) air hose