If you plug a controller in it disappears and windows starts playing the 'new usb device connected' sound effect. Would not recommend in the slightest.

I like how slim they are. Works great, flexible size. They’re ice blocks dude.

I use it in one of those big, hard-sided, rolly, 40-quart coleman coolers. One unit works fine and keeps my second lunch chilled all the way until 3pm.

Stays frozen for around 8 hours and keeps sandwiches cold till at least lunch. I know there are some folks mentioning malformation with freezing and thawing - haven’t seen that and at least two are used every single day. my lunch sack is insulated.

It makes a lot of noise in a cooler wiggling around. Now they are more square and they don't stay completely flat (the new ones sort of bulge).