Get stronger, healthier hair with BioSilk Silk Therapy Original Serum. It's made without parabens for safer use. This BioSilk silk therapy serum can be left in and does not require rinsing. Use it to repair split ends and provide future protection. This paraben-free hair serum is suitable for all hair types. This includes dry, oily, straight, and curly. Keep this formula on hand when you want hair that feels both soft and luxurious. It has not been tested on animals. The serum is available in a 5.64 fl oz bottle that's recyclable, making it environmentally friendly. A contoured design makes it easy to hold and dispense. This hair serum can even be used as a skin conditioner. It can be used as often as needed.