Section 2(1)(iv) in The Ministers (Allowances, Medical Treatment and other Privileges) Rules, 1957
(iv)'first class compartment' means a two-berthed or four berthed first class compartment or an air-conditioned coupe or a four berthed air conditioned compartment [or a coupe in the air-conditioned sleeper class;] [Inserted vide MHA Notification No.14/30/70-Public-I dated 2-2-1972.]