I've gone through a couple bottles of Kontak over the years. Like it, works great, but is just too expensive. Caig DeOxit D5 cleans just as well at a fraction of the cost. Alcohol can be used (although the D5 is far more effective), but stay away from rubbing alcohol which typically contains lanolin and/or other skin softeners that will leave a film. Use a 95% or higher purity isopropyl alcohol instead.