... audio baby monitor,315Hz/433Hz optional,use battery,easy use,sound activated,factory offerSpecifications:Remote Range:50-80M (in open ... .Once baby is crying or other sound,Receiver will be activated to sound imitated baby crying;Sound Level: 92±5Db;Frequency: 315MHz ... Crying Sound are both adjustable;Battery Stand-By Time: 3-6 Months;ABS Environmental Material,conform to European,American,Asia,Ocean, ...