1. This is an efficient air conditioning system leak detection tool. 2. Pre-filling fluorescent dye into A/C system, when system leaks, the dye will stay at the leaking site till refrigerant diluting in the atmosphere. 3. By using the newest air-cooling and heat-venting device with patent worldwide, the temperature inside the lamp c an be controlled at low level to extend the bulb life and to reduce potential harm for the operators or components when detection is performing. Patent No./Country: 1. America No.6068385 2. China No.331902 3. Taiwan No. 145198