Redken Glass 01 Smoothing Serum is an oil-free serum that adds shine and flattens frizz while giving a smooth finish to any hair type. It repels humidity and adds a luminous shine. To use, apply 2-3 drops into your palm, rub together, and smooth through wet or dry hair. This is 2.0 oz bottle with some missing. please see pics. estimated at over half full.