Pet Resolve Extra Dog Training Collar for the Shock Only System with the Orange Border on the Remote. THE EXTRA COLLARS FOR THE BLUE SYSTEM THAT HAVE A BLUE COLLAR ALSO WORK WITH THE ORANGE SYSTEM SO PLEASE PURCHASE THEM ONES INSTEAD. THEY WON'T VIBRATE THEY WILL JUST WORK EXACTLY THE SAME AS THESE ONES WOULD WHEN USING THE ORANGE TRANSMITTER, THEY WILL ONLY VIBRATE IF YOU HAVE THE BLUE TRANSMITTER AS WELL. ADDITIONAL COLLAR: Extra collar for the Orange Pet Resolve dog shock training system with the orange border on the remote to take it up to a 2 or 3 dog system.