ECCO's most compact and popular line of back-up alarms, the 500 series provides a cost-effective warning solution with ECCO quality and reliability. A glass filled nylon housing with epoxy encapsulated electronics provide exceptional durability and protection against moisture, dust and vibration. ECCO's 500 series Smart Alarm® measures ambient noise and adjusts sound levels, creating a volume that is safe without being annoying or contributing to noise pollution. Smart alarms eliminate the need for constant manual adjustment and help prevent intentional alarm disconnection.