Product Dimensions:9 x 1.5 x 0.5 cm; 18 GramsClosure:Swivel ClipColour:BlackQuantity:1batteries required:NoBatteries Included:NoItem Weight:18 gIs your dog always behaving the way you want it to?Safety Dog Whistle: This dog whistle is made of safe and durable stainless steel. Ultrasound frequencies attract the attention of dogs without damaging their hearing and without any health problemsAdjusable Frequencies: Different dogs respond to different frequencies. Our dog training whistle has a nut and screw that would adjust the frequency when turned. Notice your dog's reaction to each setting until your dog exhibits the strongest reactionAnti-Loss Dog Whistle: With the matching whistle strap, you can hang your dog whistle around your neck and have it ready to hand at all times. This also minimises the risk of lossProfessional Dog Training: You can easily teach your dog unlimited commands by adjusting the different ultrasonic frequencies, such as stop barking , sit, come, lay down,stay and moreTrain Your Dog with Patience:The dogs training whistle wouldn't make your dog understand your instructions immediately, first use the dog whistle to capture the dog's movements, then blow the dog whistle and give rewards, one sound corresponds to one action.It requires multiple training for your dog tolisten to your commands,please be patient.