4Z8 callsign series for foreign amateur radio operators
4Z0, 4Z2 and 4Z3 Vanity callsigns
Class A (Advanced): 4X1 and 4Z1 callsign series
Class B (General): 4X4, 4X5, 4X6, 4Z4 and 4Z5 callsigns (and a 2 letters suffix).
Class C (Novice): 4Z9 callsigns (3 letters suffix)
Class D (Technician): 4Z7 callsigns (3 letters suffix) – no longer issued.