John,Kroil's amazing stuff..First time ,I saw it: early 80's, supplied to Vandenberg AFB. ( Was neighborhood friends,with painters union president & family,locally) This is good stuff, then & now. Had better luck with PB Blaster, than WD 40. ( both have their advantages, actually a thread here on WD40's versatility..) The Kroil ( when I had access to free,lol) just seemed to penetrate the best.