I am pretty sure they are a 3/8" semi dome tweeter. They are roughly the same physical size of a 3/4" dome tweeter, but you can fit most 1" tweeters in the bracket with a little filing of the plastic tweeter housing. Or you can use a piece of radio back-strap and bend it to match the screw holes on the back side of the grille, and to accept the larger tweeter. Its very easy to pop the tweeters out and see if the new ones you're thinkin about will fit.