K9-400 K9 HANDLER TACTICAL 1207m Remote E-Collar 2 DogsK9 400 K9 HANDLER TACTICAL 1207m Remote E Collar 2 Dogs The K9 400 K9 Handler is a 1207m range trainer loaded with unique features like a 33" bungee collar, making it the most humane and effective trainer available with the smallest rechargeable dog training collar receiver in the world. But, dont be fooled by the small receiver size 2X1. 5X1 2. 4 ounce, it provides plenty of stimulation for most dogs. The unique COS (control of stimulation)