The shimano mineral oil bleed kit is a non toxic oil bleed kit that is used to keep high end bikes well maintained shimano use mineral oil in their brakes as it is non corrosive and non toxic its even environmentally friendly so you can feel good about using it bleed your brakes every six months to prevent air build up or to replace broken down fluid shimano mineral oil bleed kit features all you need to bleed and maintain your shimano hydraulic disc brake system kit includes shimano h