Features of the Carhartt Men's Base Force Heavyweight Crew Heavyweight, force base layer Built with force FastDry Technology to wick sweat and dry fast Built to move with rugged flex stretch Technology Smooth flat lock seams and tagless label for comfort Concealed thumb loop Stain fighting fabric stAres down heat and grime Takes the fight to odor and wins in a Technical knockout Superior wicking action makes perspiration a memory Fabric Details 80% Polyester, 20% Wool