The ZM1030 is a red coated numerical nixie tube manufactured by Valvo. It is a bi-quinary model, which means the tube has two anodes and 5 cathodes, every cathode is sharing two digits, controlled by the anode seperated by a screen grid. This feature makes the tube much more difficult to drive and so less recommend for projects. The ZM1030 was manufactured by different comapnies and there is also a clear glass version, the ZM1032. The B5025 is very smiliar