The Eagle Eye VM-100 Battery Voltage Monitor is a simplistic & inexpensive battery monitoring system designed to monitor battery string voltage for over and under voltage conditions. The VM-100 Battery Voltage Monitor is used in 24V, 48V, 125V, and 250V applications - and reads battery bus status, detects out-of-limit conditions, and provides alarm indications per user settings. The unit is equipped with four (4) Form C Contacts - Two (2) Form C contacts for over voltage & Two (2) Form C contacts for under voltage.