This insulator set fits Mack Universal and Mack E6 applications and is sold in a pack of 4. It acts as a buffer between components, cutting down on heat transfer, vibration, or noise in the assembly it protects.Interchanges:Mack 107MF21P10Mack 107MF21P4FMT-3980This unit is sold in packs of 4.FeaturesPack of 4 insulatorsFits Mack Universal and Mack E6 applicationsTech SpecsSell pack: 4 piecesUsed in this Truck Cab modelCooling System Parts & Diagrams