The GA12 is a large Nixie tube distributed by Swiss manufacturer Cerberus, though it was not originally produced by them. Instead, it is a rebranded version of the GR10J tube manufactured by ETL in Great Britain as part of their DIGITRON line of display tubes.

This tube stands out for several reasons. Firstly, it features a copper-colored anode, an unusual characteristic shared by only a handful of other Nixie tubes, such as the XN12. Secondly, the base of the tube is wrapped in black shrinkwrap, concealing the internal electrode connections to both the anode and cathodes. This covering might serve a functional purpose, as occasional discharges can occur at the electrodes themselves, and the shrinkwrap could be intended to hide it in such cases.