Detects all kinds of halogen refrigerants Sensitivity adjusted at any time and it can be adjusted automatically to the best state of detecting. Audible and visual leak indicators Inner precise IC with Ultra-low consume circuit design, more stable, longer battery life. Tri-color visual display of battery voltage. Excellent sensor, high sensitivity, longer use. Storage pouch included Halogen Leakage Detector requires (4) AAA batteries (NOT included).