My instrument is fitted with old fashioned ball joint lever mechanisms which have become worn out over the years. Having previously used some lighter petroleum distillates for lubricating these joints, I've always found the results unsatisfactory. The action was jittery, noisy, had noticeable play and adjusting the screws holding the joint together either made it too loose or it would completely seize.
The JM Nr. 15 was designed exactly for my use case. Applying the product resulted in much smoother and quieter lever action without a compromise of reduction in speed. Even the play has lessened and I could tighten the screws further.
The lifespan of my old instrument is extended thanks to this lubricant.