What It Is:A refill that fits into the glass bottle of your existing Re-Nutriv Ultimate Diamond Transformative Brilliance Serum.What It Does:Powered by Estee Lauder's Black Diamond Truffle Extract and youth-sustaining technology, this extraordinary serum helps fortify skin for a firmer feel and a visibly more perfected surface. The transcendently weightless, delightfully indulgent fluid absorbs quickly to refresh skin and help restore a plumper, smoother feel. With every touch, your diamond-brilliant skin awaits. Dermatologist tested. Ophthalmologist tested. Won't cause breakouts and won't clog pores (non-acnegenic).Key Ingredients:From a single master grower in the southwest of France come fresh, never-frozen whole truffles from the best, "Extra Class" grade. Harvested at the season's peak. Extracted within days for maximum potency. The power of each truffle is unlocked through an intricate process of fine-milling and ultra-purification, commissioned by Re-Nutriv. The exclusive Black Diamond Truffle Extract has been shown through in vitro testing to help skin stimulate its natural energy and visible vitality.How To Use It:- To refill existing glass bottle, twist collar to unlock, pull collar up to reveal empty refill, then replace empty refill with new refill. Return collar onto bottle and twist to lock.- Apply serum to clean skin morning and night. Avoid eye area.