1938 dual-wave battery / mains portable set. One of the first Stella sets manufactured by Collier & Beale after RCNZ dropped manufacturing of private-brand sets in 1937. Blue (vinyl? tolex?) covered with a 6V vibrator pack built in making it capable of running from a 6V battery or 230V mains - and was both advertised as perfect for the beach or bach and as a set for homes that did not yet have 230V mains.
Looks-wise it resembles a vintage guitar amp almost more than it does a radio and was quite a departure from the previous RCNZ designs.
General Construction Notes for Collier & Beale Ltd:
Model numbering followed no real sensible scheme until around 1940 - and prior to 1934 apparently no model numbers were assigned at all.
From 1940 a 3- or 4-digit system was employed where the first digit indicates the number of valves, the second digit is the number of bands and the third is the year of manufacture. From 1950 the last digit became two digits, eg: 5151 is a 5-valve broadcast-band only from 1951.
From 1957 model numbers were replaced with model names, ie the Pacemaker Buffalo - which makes the year of manufacture hard to determine unless service info is consulted (although C&B often released service info after the radio, and the date on the service info was for its release, not that of the model.