The IFR6015 is a compact, lightweight and weatherproof unit designed for testing Transponder Modes 1,2,3A,C,S, TCAS I, II, and Military E-TCAS, TIS as well as DME/TACAN. IFF Modes 1,2 and TACAN are standard on all new units. For upgrades to existing units contact VIAVI Solutions. NSN: 6625-01-574-2423.