The original, time-proven formula developed by Jim Brobst and produced under exclusive license. J-B has been getting burned-on, caked-in powder residue and copper jacket fouling out of gun barrels since the 1960’s, and hasn’t damaged an inch of rifling yet. Today, J-B once again proves itself a champion by the way it easily cleans the dirtiest, moly-fouled barrels. A unique combination of ingredients and a one-of-kind, multi-step mixing process give J-B its special characteristics. They work together to cushion the abrasive action; the soft paste liquifies as you use it, then wipes out of the bore easily.