Reflux milk whilst out and about!

[Smellybears]

Hello!
Just wondering what the best way to make up anti reflux milk whilst out and about please? I have a perfect prep machine but have no bottle warmer. He’s on 4ounces.
Thank you!

I’m not sure on that one. Have you tried taking the powder and a flask of hot water?

Hopefully someone who knows more will be along soon