Review on Portable Stainless Steel Camping Mug - Collapsible Cup with Keychain, Ideal for Outdoor Travel, Demountable Design, 75ml 150ml 250ml (L) by Justin Woolley

I got the large version because a lot of these mugs can barely hold anything and I love a cup of tea on a cold morning. It's definitely a good size for it and it seems to be made out of some pretty good materials. It doesn't leak (as long as you open it all the way and tighten it), but a lot of the edges are really sharp and have little burrs. The non-functional but easy-to-grasp edges are also very sharp. I expect many finger cuts opening and closing this mug. I understand that the edges of the fold shouldn't be rounded or leaks can occur, but given the sharpness they have I think they actually scratch the sliding parts and speed up the leak! I have a few trips ahead of me to try it but I don't know how well it will break.