PetSpy M86 Extra Dog Training Collar - Replacement Part for 1100 Yards Advanced Dog Training Systems M86-1, M86-2 and M86N Compatible with PetSpy Advanced Dog Training Collars: model M86-1, M86-2 and M86N COLLAR SIZE: Width: 3/4", Max Length 27", Min Length 8" - good for dogs 10-140 lbs IT WILL NOT WORK with PetSpy M686, M919-1, M919-2, P620, P620B PETSPY ADVANCED Extra Dog Training Collar - remote transmitter and charger are not included 3 TRAINING MODES: Shock, Vibration, and Sound Stimulations; Range up to 1100 yards