: This article is a . You can help My English Wiki by expanding it, or perhaps you could contribute to discussion on the topic. Jay Null, better known by the alias Doctor J, is the engineer and creator of the Wing Gundam and Heero's mentor. His distinguishing features include eye lenses, leg braces and a prosthetic right arm. Doctor J is voiced by Minoru Inaba in the Japanese dub and Dave "Squatch" Ward in the English.