1940 5-valve broadcast-band radio.
Serial number above shows manufacture in 1939, however 1939 Courtenay models all had large aero dials, slide rule dials were not introduced until 1940. The ARTS&P label is also indicative of 1940. Its likely that this set was an early manufacture for the 1940 season.
General Construction Notes for Radio Corporation of New Zealand Ltd: The first digit of the serial number typically indicates the year of manufacture of RCNZ chassis' (although not the decade - that requires a little knowledge of the valves, construction, etc). Sets from around 1934 onwards were often (but not always) constructed in a distinctive pressed 'baking pan' style chassis, seemingly unique to RCNZ.