Huaer Teeth whitening gel HR-TWG15:Prefilled with 35% Carbamide Peroxide. 16%, 22%, 35% or 44% percent is also available Huaer Teeth whitening gel HR-TWG15 Prefilled with 35% Carbamide Peroxide. 16%, 22%, 35% or 44% percent is also available Volume: 3mlWeight: 6.8g A gentle and assured way to remove internal stains,such as Coffee,Tobacco,Genetic,Tetracycline,Food Coloring,Aging .