spark plugs are not voltage specific. Ie not 6volt or 12 volt.
Type of plug depends on the type and size of motor you have.
Dooginator ·
Aussieveedubbers · Tech Talk
https://forums.aussieveedubbers.com/threads/8866/what-spark-plugs-should-i-use-for-6v-system
Dooginator ·
Grey 57 ·