Taylor 4 Oz. Air Tool Oil is specifically blended to remove harmful deposits that can build up in your tool. It is also formulated to emulsify with moisture to protect internal steel parts and bearing from rusting. The most effective time to oil a tool is right after use. Put a teaspoon or two in the air inlet, run the tool for a second or two to coat all internal parts. Now the tool can be stored for long periods, preferably away from dust and dirt.