Primal Wear Tattoo Arm Warmers polyester, Lycra High Performance Sport Fabric Sizes = Bicep Size (Unflexed). Made from wind resistant Poly/Lycra, these arm warmers feature a gripper elastic hemmed bicep cuff and an elasticized, rolled-finish wrist cuff. The bicep cuff is specially designed for high intensity sports, preventing even the slightest slippage.