hugheshilton
* Ace Member *
I have never known what zipper top meant... can someone help me with my ignorance...
I've asked this question before so I think I finally know! It's where the top of the disc has little tiny circular grooves like a record. I think if you run your fingernail down it, it's supposed to make a certain sound, but you can see it pretty easily in good light too. I think it's supposed to be the sign of a new top mold piece because it wears off the mold after a while.