We highly recommend that you use only IM Corona flints in your Old Boy pipe lighter. They are designed specifically for Corona pipe lighters and will ensure a long life and continued reliability. Using lesser flints could damage your new pipe lighter and in some cases, void your warranty. Always bleed your pipe lighter before refueling. This will help prevent the built up of propellants in the pipe lighters fuel tank which will eventually cut down on the lighters fuel capacity and cause the flame to flicker.