Cover up to 50% gray hair with Clairol Professional Beautiful Collection Advanced Gray Solution Semi-Permanent Hair Color. No ammonia, no peroxide and gentle enough to be used right after relaxing. With Advanced O2 Technology. this hair color features twice the coverage for twice as long.* With no ammonia or peroxide and by replacing ammonia with natural oxygen, this gentle semi-permanent hair color can last for up to twelve washes. Also all shades cover up to 50% gray effectively for up to twelve shampoos.