Size:1-Pack Easy to use – set in lowest spot where waterleak may occur. Detects water 1/16′ deep. Ideal for use in areas not usuallyobserved: Water Heaters – Behind Washing Machines or Dishwashers – UnderRefrigerator for Ice Makers – Under Sinks – Sump Pumps of inside pits -Toilets – Behind or near media systems. Provides early warning of potentiallycostly water damage. Re-Useable Water Leak Alarm RWD21 Sensorand alarm all-in-one Loud audible alarm Economical way to defendagainst water leaks Never be surprised by a leak or flood again! The HoneywellRWD21 Single Use Water Leak Alarm automatically goes off when water comes intocontact with it allowing you to respond to leaks and floods quickly andprevent disastrous damage caused by unknown water exposure. Great for placingaround water prone areas such as sump pumps, water tanks, burst prone pipes,or even under the sink. Honeywell’s water defense system and water-sensingalarm offers superior protection against leaks and water damage in your homeand office. Add peace of mind with a water leak alarm. Features: Unlimited usespot detector; easily re-sets for re-use Easy to use near water heaters, sumppumps, under sinks, dishwashwers Water sensor and alarm all in one Economicalway to defend against water leaks in multiple locations throughout the homeLoud audible alarm Alarm sounds for up to 24 hours (dependent upon batterylife) Low battery chirp Requires 9V battery (sold separately) See all Productdescription