These one hour strips are dry strips (not Gel) and peroxide free. The difference between dry strips and gel strips is that they are very sticky and can stick to your teeth for 2 hours. They have great resistance to the dissolubility of saliva and guarantees enough time to act to achieve an excellent whitening effect. You can even drink and swallow while using the strips The whitening effect can be seen using the new generation strips for a single time and continuous use will make the teeth even whiter. whitening strips the ingredients Sodium Chlorite, ETDA, Menthol, Hydroxypropyl Methylcellulose, Stevioside,Glycerin, PVP (K30), PVP (K90), Alcohol. Expiry 31/12/2020