Originally Posted by dae06
I myself can not tell if the bottle is a twist off or screw off with the cap on,
It's pretty easy to tell. A couple hints:
* Twist off caps almost always have some sort of indicator - an arrow or the word "twist" or something to that effect
* Twist-off caps have visible "threads" on the sides, running at an angle to the bottle itself.
Of course, if you're in the store and the bottles are safely enclosed in a cardboard 12/24 pack, this won't do you much good.