These collars will fit the following products:
Petsafe 250m Trainer
Petsafe 400m Trainer
SportTrainer 350m (SD-400E)
SportTrainer 450m (SD-425E)
SportTrainer 500m
SportTrainer 700m (SD-800E)
SportTrainer 700m (SD-825E)
SportHunter 800m
SportTrainer 1200m (SD-1225E)
SportTrainer 1 Mile (SD-1825E)
SportDog No Bark 10R
SportDog Pistol Grip 400m Trainer
SportTrainer 1525E
SportTrainer 1825E