This hose coupler seal is built for air brake systems and sold as a pack of 10 identical units, fitting Mack applications. It seats between hose ends and couplers to keep the joint sealed against pressure loss. The multi-pack quantity makes it convenient for servicing several couplers in one job.Interchanges:745-213630NCaterpillar 1F8311Mack 745-213630MCS-4519This unit is sold in packs of 10.FeaturesHose coupler seal for air brake systemsSold as a pack of 10 unitsTech SpecsSell pack: 10 pieces