More amazing experiience with the Zentek vest. It was 33 F . I went out in my scull for a few hours of beautiful winter rowing.I wore a cotton long sleeved T shirt and my vest-- and leggings. It took a few minutes for my hands to warm up, so I could feel my fingers-- kind of important when you're rowing. But I was warm inside my vest-- yet I could feel it was cool on the surface. I have tried lots of athlectic clothing. It's unlike anything else.