Under Armour Men's HeatGear Armour Zonal Compression Short Sleeve 73% Nylon/27% Elastane Imported That print isn't just there for show: it strategically targets muscle zones to give you stronger compression where you need it Tough, lightweight HeatGear fabric, with all the performance benefits of UA Compression Stretch-mesh underarm panels deliver strategic ventilation Updated ergonomic design keeps seams off high abrasion areas & increases durability 4-way stretch construction moves better in every direction