Wahl Blade Oil is used to keep blades lubricated, which helps them run cool and stay sharper for longer. We recommend oiling your blades after each use to help them last longer and keep performing their best. To keep your blades performing their best, we recommend you oil your blades after each use. Place 3 drops of oil along the top of the blade's teeth at the left corner, right corner, and center of the blade. Turn the clipper to its side and place 1 drop of oil at the heel of the top blade. Repeat with 1 drop of oil on the other side. Turn the clipper on and let it run for a few seconds to allow the oil to work its way into the blade sets. Use a soft cloth to wipe away any remaining excess oil.