The ion bonder was an energy weapon owned by Nyssa of Traken, allegedly based on ion energy. It shot a green ray.
Stunning was its main effect, even if its ion rate could be stepped up. It was used by the Fourth Doctor as well. (TV: The Keeper of Traken [+]Johnny Byrne, Doctor Who season 18 (BBC1, 1981).)
The weapon was waterlogged on Castrovalva. (TV: Castrovalva [+]Christopher H. Bidmead, Doctor Who season 19 (BBC1, 1982).)
The Fifth Doctor and Nyssa used an ion bonder whilst effecting repairs on the TARDIS. Tegan Jovanka had it when she was transported onto the Exemplar and used it to get through locked doors. (AUDIO: Zaltys [+]Matthew Elliott, Main Range (Big Finish Productions, 2017).)
The Curator carried one and was able to use it to make a cup of tea. (AUDIO: The Artist at the End of Time [+]James Goss, Once and Future (Big Finish Productions, 2023).)