Yes, we got the other Brite Tap attachment for the Rubbermaid thermos but it was more of a little cup waterer rather than Brite Tap's older nipple waterer. We're using the newer Brite Tap cup attachment on one Rubbermaid and still use the old Brite Tap nipple waterer on a second Rubbermaid -- all our birds prefer the nipple waterers. We moved the two small Rent-a-coop single nipple chick waterers outside but the small Rent-a-coop quart tanks are not insulated like a thermosThere is
There is a different nipple attachment for that kind of cooler that you can get- I have one. I agree, having a cooler that I can put a big chunk of ice in to keep the water cold in the heat is GREAT!

Our summers get brutal and in past years have lost a couple hens to heatstroke. We bring the hens into the house during heatwaves now.