Notice this as I was practicing yesterday,

They turned on the Black lights and one slug glowed and the other did not. The one that did was about 12 years old, the one that did not was new.

Not that I care about glowing slugs, but maybe someone can tell me what the difference is? Material maybe? New one is a Vise

Next, as I do deeper into the 3 game set or more if practicing, it seems that my thumb starts to stick on the inner part of my thumb and I have to use powder to make it slick again. Man hands are on the dry side for sure and I use turbo Tape on the top of my thumb.

Can someone explain the two different types of thumb slugs and why there is a difference in material please.

Thanks