Peresvit Mens Rush 3D Performance Seamless Compression T-Shirt Short Sleeve (Small/Medium, Navy) 93% nylon/7% spandex. Imported The unique Peresvit 3D Performance technology allows different levels of compression, cooling and ventilation for each body zone; The super elastic fabric provides a second-skin fit for any body type; PS Dry Max technology helps wick moisture away; PS Thermo Balance advanced temperature regulation system allows you to stay warm or cool as needed; Antibacterial and anti-odor properties.