Blue Juice valve oil is the most popular valve oil on the market. Suitable for piston and rotary valves. It was developed by a chemical engineer who is also a trumpet player to give fast valve action and staying power to minimise the need for re-lubrication. It has built in inhibitors to retard bacterial growth, especially when it is a long time between clean outs! It is also non-corrosive to metals meaning that it won't harm your instrument.