XL

Took this on a 6-hour hike and my water was still cold at the end. The premium insulation really does hold up, way better than the cheap tumbler I used before.

Took this to the office and my coffee was still hot at lunch, which never happens with my old mug. The insulation is no joke, and it fits my cup holder without wobbling.

Filled it with ice water before a hike and there was still ice rattling around six hours later. The insulation genuinely holds up, and it hasn't leaked in my bag once.