Propel bottle opener

My neighbor drinks these black cherry Propel waters, who's caps are difficult to remove.  We were over there playing cards last week, and she was struggling with some piece of rubber she uses to grip the caps, so I told her I'd make her something for opening those.

I keep the 80 splined version from which this was derived in the silverware drawer, which I use for opening half & half cartons, so I thought she might like this.  She tells me it's amazing and that she's very happy with it.