Smile whitening kit does not act on: deep intrinsic stains of enamel and dentin, plaque, dental restorations such as fillings, inlays, crowns, veneers etc., stains due to drugs, poor oral hygiene, smoking, alcoholism, tooth decay. Do not immerse the LED mask cable in water. Do not insert the cable plug (LED mask) in non-original electrical outlets (Apple / Android) and that are not in compliance with the law. Do not expose the product to humidity or rain. Do not touch the cable (LED mask) with wet hands. Do not use the product if it has been damaged, if it has suffered a strong knock or a fall. Disconnect the cable when not in use. Store the kit in a dry, cool place, away from heat and sunlight when not in use. Avoid penetration of dust or other materials into the LED mask.