Busy girls don\'t wait for their Wonder self-tan. Combining the best self-tanning technology with Anti-Aging Q10 and hydrating skincare ingredients. Wonder Serum ultimate Express Formula is time activated so it\'s up to you! As with the Wonder Serum original, this silky, skin-nourishing serum develops into a lasting flawless tan in as little as 1 hour, instantly leaving skin with a luxurious iridescent bronzed finish Skinny Tan Wonder Serum has 96% natural ingredients for a flawless finish every time. Skinny Tan is always paraben & sulphate free. Vegan friendly and cruelty free. Leave to develop for 1 hour for a light tan, 2 hours for a medium tan or 4+ hours for a deeper tan.