OOoooooK.

Long story short. Cara Guyot told me that the plain old Nalgene caps don't fit their bottles. Whether they changed the design once, twice, who knows. Either way, she agreed with me that the person wanting to know if the filter they'd like to buy will fit their Guyot bottle-- will most likely just try the Nalgene cap on the bottle on the store shelf next to the Guyot. They will more than likely be misled because the Nalgene lid is now a different thread pattern, and may possibly not purchase the Guyot bottle thinking their new filter won't fit based on this comparison. Unfortunately, this sucks for Guyot. They're great products, and I think they need to add a disclaimer telling people that Nalgene screwed around with their cap and it is nolonger a size that will fit the Guyots. This will solve some confusion. A case of one company not telling another company what they are planning.

Cheers.

-M