This is the best tuning slide lubricant for brass tuning slides, making the slide move smoothly and yet providing enough “gel” to keep the loose tube in place.
I used to use a very similar product from Selmer, but it is almost impossible to find nowadays. Luckily, Bach continues with a product that looks the same (red), feels the same and is as good as its Selmer predecessor.
I bought five bottles from Thomann in one go to make sure I have enough for a long, long time.