The Mastercool 55500-220 Electronic Leak Detector W/220V Battery Charger. Mastercool broadens it's line with it's Heated Sensor Electronic Leak Detector. The Heated Sensor technology delivers fast and accurate results while eliminating non-refrigerant false alarms. The flexible 15" probe has a patented UV Blue Light built into the tip allowing dual UV and Electronic Leak Detection. Made in USA