The Kanji in the Japanese name of Co Tanker, 硬 (Kanyō'on: kō/Kun: katai), means hard, whose on'yomi is the origin of 'Co' as well. It is also in response to Ken Panzer's Kanji forming the Japanese term for hard, 堅硬 (kenkou).
Co Tanker was once named 'Alien' (エイリアン,Eirian?) tentatively.
Co Tanker is the only BakuTech in the Convert System to have Cross Parts that lacks any details or design.