In addition to lightning-fast delivery, I am satisfied. At first I thought some parts were missing, but when I opened individual packages I found specific valve cores and caps. I bought 4 ounce weights for 33 inch tires for my boxy Chevy. Using a pickling machine placed on the valve stems will help vibrate the small balls to keep them moving. About 5 minutes per tire. I thought the car vibrated a little in front of the balls. now it drives like clockwork. Fantastic. Best money for my 35 year old truck.