I like that the SteriPEN Classic’s tapered end provides a snug fit with Aquafina style bottles. It allows you to invert the SteriPEN and bottle for convenient and thorough stirring and treatment. However, I prefer wider mouth bottles such as Gatorade, Vitamin Water or Snapple.

I tried drilling a 15/16" hole in a Gatorade cap. It worked with the SteriPEN, but to get a good seal, I had to press the SteriPEN into the cap quite firmly. The relatively sharp edge of the hole was wearing on the tapered rubber of the SteriPEN.

By heating a brass plumb bob, it can be used to widen and taper a pilot hole into a very good adaptor for the SteriPEN. Weighs less than a gram.

Gatorade cap with 15/16" hole. This wasn't satisfactory (too rough on the SteriPEN).


Gatorade cap with tapered hole. This works great.


Together with SteriPEN, inverted.


Taper used to create adaptor.


Inside of tapered adaptor before cleaning it up a bit.


Thanks for reading.

Edited by Lancem on 03/23/2012 19:31:50 MDT.

Great idea!

That's a cool idea you have there.

I have the Adventurer Opti and I really need something like this. Problem is the little LED beside the light tube. Anyone seen or know of any way to adapt the Adventurer to smaller bottles?