About the Stanley Thermos Stopper Pico de Mate Replacement Part Amazon.com: Stanley Thermos Stopper Pico de Mate Replacement Part For Classic Vacuum Insulated Wide Mouth Bottle Thermos (1.1QT, 1.5QT, 2QT) (Black/Red, Set of 1): Home & Kitchen first, it works great when you don’t use the two whitish silicone gaskets/seals. And second, in the post photo the cup-cap on the right fits on perfectly on even with the spout extended but the one on the left will not allow being fastened on.

A pseudonym-using matero “psalm723” said: I use the same pico and it’s great but the lid to my Stanley does fit with the pico on. That’s my only complaint.

i didn't grasp what he was saying but think i understand so I made this post. Here’s what I know: I bought both a black and a green 1L Stanley thermos from Lowe’s and the cap/cup both are the same just different colors and have the same expansion in the silver metal transition to being a wider diameter. These fit on either the current thermos and also the older thermos (pictured in photo).

But the cup/cap that came with a new (black) 2L Stanley thermos i bought through Amazon. (that came with what looked like a real Stanley label-packaging), doesn’t have the expansion in the silver metal; it's the one in the photo on the left and has the black plastic part.

Can you add any helpful info to this?