HEIMAN&reg; Independent Water Alarm Water Leak Detector Battery Included DC 3V with SMT ,MCU and Test & Hush Function HM-003BHS Battery included,DC3V (2x1.5V AA Alkaline Batteries),Low power consumption design,Low battery warning,Rust-proof metal probe ,long service life Bracket included,Sound and flash alarm,Correct report Applied to kitchen,basement,bathroo,With test and hush button MCU processing ,resist false alarm efficiently Comes with a manual,a mounting bracket, 2 screws and 2 anchor,can be easily installed,SMT manufacture technology ,good stability