Is there any rule about this

[Langdoj]

Hey guys. I have the vise IT system for my equipment and I was wondering if there was a rule anywhere stating I needed to have the thumb slug in my ball at all times when I throw it. I haven't been able to find anything in the USBC rules (maybe I haven't looked in the right place)

Thanks for any insight on this!

[Mike White]

Hey guys. I have the vise IT system for my equipment and I was wondering if there was a rule anywhere stating I needed to have the thumb slug in my ball at all times when I throw it. I haven't been able to find anything in the USBC rules (maybe I haven't looked in the right place)

Thanks for any insight on this!

If you don't have your thumb slug in the hole, is it safe to assume you aren't using your thumb for that shot?

The kit I purchased for Vise IT came with drill bits for 1 1/4" and 1 3/8" slugs, so unless your Vise IT is somehow using 1 1/8" slugs, the hole in the ball for the IT will exceed 1 1/4"

If you're not using your thumb, the empty hole would be considered a balance hole, which can't exceed 1 1/4" in diameter, so most likely it would not be legal.

[Langdoj]

I normally bowl 1 handed and use my thumb with a slug. The reason I ask is I like to bowl two-handed from time to time and since my equipment all has balance holes I cannot bowl 2 handed without my thumb in the ball. So to get around that I take the slug out and put my thumb in the thumb hole.

[Mike White]

I normally bowl 1 handed and use my thumb with a slug. The reason I ask is I like to bowl two-handed from time to time and since my equipment all has balance holes I cannot bowl 2 handed without my thumb in the ball. So to get around that I take the slug out and put my thumb in the thumb hole.

It sounds like you end up with just a ball with a rather large thumb hole..

So all is good.

[Langdoj]

Okay good, thanks for the feedback!

[NewToBowling]

Yep, doesn't need to be a functional thumb hole.