Graco Digital I-Moniter 2 Parent-Uni Specification.. Digital security for complete privacy- so you can't hear your neighbours phone calls andthey can't hear you! Technology 100 percent Digital Technology Digital signal for crystal clear clarity Digital security for complete privacy so you can't hear your neighbours and they can't hear you Peace Of Mind Digital power for extended range up to 600 meters (2000 feet) Out of range alarm. Low battery alarm and charging indicator light Convenience Compact parent unit with belt clip for easy mobility Docking station Pager to easily locate parent unit Rechargeable batteries