My name is Jesse Milstead of Lackey high school and my engineering team and I are desiging/creating a tracesable arrow using both a knock that lights up and a very small speaker. The speaker part is what i need your help with, we need a speaker 3mm or smaller and it doesnt matter how long it is. But the smaller the better in this case since we need to not mess with balance of the arrow as much as possible.
Thanks,
Jesse and JCD Engineering