I grew up in a tropical country, shorts and tank top weather all year round. Moving to Melbourne was a shock to the system. Winter was a rude shock. No matter what I wore, layers upon layers of heat tech, sweaters just never cut it. Chanced upon fortress from some random Shark tank video on YouTube and gave it a chance. Bought the 1/4 Base and the pants. Nothing else has kept me warmer, I dread the days I have to take them off to wash. Has kept me toasty. Love my fortresses