Alarm.com VDB750 Power Module (ADC-VDBA-PM-750)Alarm.com VDB750 Power Module (ADC-VDBA-PM-750). REQUIRED FOR DIGITAL CHIME INSTALLATIONS WITH ADC-VDB750.SKU: ADC-VDBA-PM-750Alarm.com VDB750 Power Module (ADC-VDBA-PM-750)$21.75PriceQuantityAdd to Cart