What you want to ask is what is the five-pointed star sign on the bottom of the double-gun lighter? Fuel filler. According to Zhongguancun's inquiry, the five-pointed star sign of the double-gun lighter is an international common sign, indicating that this position is the filler of the lighter, so the five-pointed star sign at the bottom of the double-gun lighter is the filler. Lighters are small ignition devices.