GooDGo&reg; Medium and Large Dogs Electronic Control Anti-bark Training Shock Collar Excellent remote control training collar for Small, Medium & Large-sized dogs, very Easy to operate 4 Functions: Instant Static Impulse, Vibration, Whistle Signal, LED Light. Water Resistant It is a Perfect training aid for your dog which can help you achieve a well trained and contented dog within days The electronic dog training system with a working range up to 800 feet The remote collar is, at present, most humane pet training tool. Use as per proper manner could train pets safely and effectively without any hurt