The ProFlex 550 Padded Knee Sleeves feature a 3-layer foam knee pad and a low-profile spandex sleeve design for enhanced flexibility and comfort. Inspired by athletic knee pads, these knee sleeves are built for movement. Soft strapless nylon spandex fits and flexes comfortably under or over clothes, providing workers with an alternative to more traditional bulky knee pads. For enhanced breathability, the back of the sleeve features mesh paneling to improve airflow and reduce sweat. For protection on both tough and delicate surfaces without risk of scratching or marring, pads are made with 3 supportive and flexible layers. First layer is an abrasion-resistant PU (polyurethane) film for durability. Next is an impact-absorbing polyurethane foam for protective support. Third layer is a gel-like neoprene comfort foam that softly cradles the knee for enhanced fit and feel. Anti-slip silicone grips along the top and bottom interior of these sleeves help keep them in place.