 "PK 1234" to "A 1234" and "JB 1234" to "J 1234"), leading to the extinction of the use of double-letter state identifiers in Malaya; a similar change was imposed on pre-1948 Pahang plates.Remaining single-lettered UMS and Straits Settlement identifiers were not subjected to the 1948 change.Following the rationalisation of prefixes in 1948, new plates registered in Malaya (and then Peninsular Malaysia) bear a "Sx ####" format, which was sufficient for use through the 1950s and 1960s.