GR-7 is a liquid that helps you regain your natural hair colour. It effectively changes grey hair BACK INTO NATURAL! The secret is in melanin – a substance responsible for hair colour. With age, melanin becomes less active, and hair lose the natural colour and become grey. GR-7 reverses that process. Just rub the liquid into your scalp daily, and you will see the effect. On the average natural hair colour comes back after two weeks of daily application. Later on, when the colour is back, just apply GR-7 once a week to keep your natural colour. GR-7 has been tested by a leading European product testing agency, and obtained a certificate confirming its effectiveness.