VEVOR Restaurant Pager System, Wireless 400m Long Range Lineup Waiting Queue Signal, Guest Customer Calling Beepers with Vibration & Flashing, 20 Buzzers for Food Truck, Church, Nursery, Hospital Outstanding Performance Long Usage Time User-Friendly Settings Wide Coverage Turn On/Off Multi-Scene Application Battery Capacity: Lithium Polymer 250mAh,Number of Sub-units: 20, Rectangular,Color: Black,Item Model Number: P30,Product Weight: 0.6 lbs / 1.39 kg,Base Dimensions: 10.7x6.1x1.2 inches / 273x154x30 mm,Sub-unit Dimensions: 4x2x0.5 inches / 102x52x12 mm