4oz is highly recommended. It is lightweight, sweatwicking, and has some stretch. Perfect for under your gear on the mountian. Designs dyed right into the fabric so it will never pick, peel, or fade away. Recommended to hang to dry.
.: 100% Polyester
.: Light fabric (4.0 oz/yd² (113 g/m²)) / (6.0 oz/yd² (170 g/m²))
.: Regular fit
.: Tagless
.: Runs true to size