Columbia Minx Shorty Omni-Heat. I was wearing those boots for about only 2 months and then the holes started to appear on the sides. Holes are only in the top layer, they don't go through. After the second big hole was formed, it was clear why. The toes in the boots protected with a kind of plastic insert between the top and the insulated layers, thus, in the place where this plastic insert is finishing the hard edg of it brakes the top layer of the boot. This thing happened on my both shoes. So, the bad design cause this problem. Unfortunately...Very dissapointed! Don't buy those boot!