The Pearl Izumi Women's Transfer Sleeveless Baselayer is designed to keep you cool and comfortable even on those hot summer days. P.R.O. Transfer fabric facilitates the evaporative process by rapidly moving moisture away from your skin to outer layers, while activated charcoal in the front panel fabric further speeds dry time and cooling. In back, mesh panels maximize ventilation. Wear this sleeveless baselayer under a short sleeve jersey during the heat of summer, and then add it to your cool weather layering system during chillier months.