MAGURA Royal Blood Mineral OilAll MAGURA brakes use low viscosity mineral oil (Royal Blood) as hydraulic medium. Contrary to DOT brake liquid it doesn't irritate human skin or damage the paint on your frame. Biggest asset: It does not absorb water and actually lubricates the whole system. Regular bleeding of old brake liquid is therefore not necessary! 5 Years leak proof warranty by using MAGURA Royal Blood. Please pay attention to the safety instructions on the packaging working