[EASY TO USE]: Each time you use different flute methods to specify the commands such as "Do not move", "Sit down" and "Come". For example: "Do not move" "Two short sounds" "Sit down" "One long and one short". You can easily teach your dog unlimited commands by adjusting the different ultrasonic frequencies. Please keep your whistle command consistent, when your dog does it right, give him a snack reward, approach to make your dog a listening and obedient friend. [ADJUSTABLE DOG WHISTLE]: 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 reaction. [EFFECTIVE DOG TRAINING]: Your pet can hear the dog whistle up to 25 meters away even if they can't see you! Train your dog with different commands and get them to follow your instructions. (Sit, Paw, Lay Down, Up, Heal). [ABSOLUTELY SAFE]: The dog whistle body is crafted with stainless steel coated with a protective lid to prevent dirt, damage, and accidental loss. It is extremely easy to wear around your neck with our matching black lanyard. [NOTE]: Please note that this dog training whistle wouldn't make your dog understand your instructions immediately. It requires multiple training for your dog to listen your commands. Use the rewarding-positive-behavior approach to make your dog a listening and obedient friend. When the dog is 3 to 7 months old the training effect is the better. Colour:As Shown Material:Stainless steel Package Contents: 1 * dog whistle Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.