NSF Certified Dow 111 Molykote Valve Lubricant & Sealant is the recommended lube to use in your Espresso Machine rebuild. Very good for assembly lube as well as maintenance on your Piston Rod Seal, good to treat most O-rings throughout the machine as well. Because it's NSF certified it's food safe! This 6 gram packet will last a long time, use it sparingly - a little dab will do ya!