View attachment 154256
I use this out on the bike.
Fits perfectly into the bottle cage

Made by a company called Grunwerg, bought mine locally but saw similar on Amazon.
It went "a bit funny" after I put it in the dishwasher but still works ok.
This is the one, the only one.
Kathmandu used to sell it, and it is still on their
australian site, but I can't find it on the UK site anymore. Glad to see it is still out there. Not sure how long it keeps things warm, but I have never had a cold coffee out of it, and a barista once said "I've made it extra hot to keep it warm", and I couldn't drink it for hours. It's better than the Lifeventure one (I have one of them, too) as when you take off the waterproof cap, there is a normal thermal coffee mug sippy lid inside, so no risk of spilling and it doesn't chill down as while you are drinking.
Just checked, it would rattle in my bottle cage, but i just use the carabiner to attach it to my saddle bag. probably only applies with a carradice though.