GROOVYPETS All Rechargeable Remote Dog Training Shock Collar with Seperate Shock and Vibration for 2 Dog Training Rechargable receivers, auto sleep mode on the receiver with red LED light Separate Vibration for each dog and both dogs Shock buttons for each dog;shock levels: Low (L) or High (H) Rechargeable remote w/power switch, remote range up to 600 FEET Nylon straps fit small to large neck size(6"-25"/15CM-64CM)