Is a fine light blueish oil, with extremely good lubrication qualities. Suitable for the valves of all brass instruments.Especially for Monel and or Steel piston valves.
Love the oil. I use it on all my horns and have never had an issue w/ sticky valves. My only complaint is that they still have yet to perfect a cap that is leak-proof. I always transfer my oil into another bottle before placing in my gig bag.