Hetman Rotor Lubricant is for musical instrument rotors and valve casings. The formula improves valve seal and will not swell rubber valve bumpers.All Hetman Musical Instrument Lubricants offer superior lubricating qualities, are longer-lasting than other lubricants, and are completely compatible with conventional petroleum-based lubricants, thereby avoiding potential gumming problems. The viscosity of each Hetman Instrument lubricant is carefully formulated for its specific purpose and assures both fast, positive action and vital protection against wear and corrosion.The included long-tipped precision needle oiler facilitates application of Hetman Rotor Lubricant through slide tubes.