OS1st PS3 Performance Patella Sleeve Sports Medicine : The OS 1st PS3 works to relieve pain associated with Patellar Tendinitis or Jumpers Knee. This sleeve is made with lightweight material infused with Compression Zone TechnologyA(R) to apply graduated compression to the patellar tendon. You can easily wear this sleeve under clothing due to its sleek design. A hypoallergenic gel helps keep the sleeve in place when you are active without causing irritation. Pack this sleeve away easily in your gym or travel bag. Can be worn comfortably under clothing during running or recovery. Helps reduce swelling. Helps ease patellar tendinitis related pain. Sleeve material is moisture-wicking for enhanced breathability.