Everyone needs a long-sleeve technical tee—like the Black Diamond Lightwire Tech T-Shirt—to say comfortable when we're playing outside across three seasons. The polyester-stretch blend is moisture-wicking and quick-drying to keep us cooler in warm weather and warmer in cool weather. The fit isn't too tight or too bulky, and the raglan sleeves and underarm gussets keep us limber when we're climbing or hiking, trekking or training. That's the versatility we're looking for in our long-sleeve tech tees.