This listing is for One Case of (12) Cans De-Ox-Id Premium contact cleaner. This DE-OX-ID Premium Electronic Contact Cleaner, is in a 4 ounce Spray Can and comes with a long plastic tube to you can get to those hard to reach areas like switches and potentiometers. NOTE: This is a class 3 Aerosol class ORM-D which has to be shipped via surface mail, so I can only ship within the United States via USPS which the default shipping cost will cover. Please allow 7 to 10 Days for Parcel Post ground Shipping. In some cases it may take several weeks as the post office has been slow with ORM-D Ground Shipments. There is nothing I can do about this, so it may arrive in a week or it may take more time depending on your location.I have been using this product for many years now and it is a fantastic product. A virtual Radio Technician in a can!I can tell you that every radio I test gets the full De-Ox-Id treatment before I even power them up. I clean all the band switches, potentiometers, relay contacts, and tube sockets.I have found that most of the problems associated with the vintage gear can be eliminated with this treatment! It is amazing to see the difference in operation after a good cleaning with De-Ox-IdThere are other products on the market but De-Ox-Id seems to work the best.This is one reason it is classed as a Level 3 aerosol as opposed to a level 1 such as a similar product called De-Ox-ItIt is a Solvent less, contact cleaning treatment compound, with active ingredients to counteract oxidation. It lowers contact resistance, inhibits arcing, and lubricates and protects against corrosion.It is made for use on connectors, sockets, potentiometers, switch contacts, battery connections, telescoping antennas, relay and thermostat contacts. It Should be applied sparingly on dirty, dusty, and heavily oxidized contacts. Best results are obtained with small amounts.I have found that after spraying the part to be cleaned, you can use compressed air to "dry" out the treated area before applying power to circuits with high voltage. Circuits with High Voltage should not be wet when the power is applied.This Product Features Long lasting protection for electronic and mechanical components, and unlike some other inferior products, it contains no silicone.