Robinair's 18470 is a POE labeled manual oil injector that enables the user to inject POE type A/C system lubricant back into the vehicle's A/C system. The injector holds 1/2 ounce of oil and features a smooth acting plunger for precise control. The injector is equipped with a low-side R-1234yf service coupler that allows the user to connect to the low side of the vehicle's A/C system. Oil can be injected either before charging or after charging the vehicle's A/C system.