Looking for a lightweight long sleeve shirt that will keep you cool and comfortable all day long? Look no further than the Under Armour HeatGear Armour Men's Long Sleeve shirt. Made from super-light HeatGear fabric, this shirt provides superior coverage without weighing you down ...Looking for a lightweight long sleeve shirt that will keep you cool and comfortable all day long? Look no further than the Under Armour HeatGear Armour Men's Long Sleeve shirt. Made from super-light HeatGear fabric, this shirt provides superior coverage without weighing you down.