Features: PACKAGE CONTENTYou will receive 2 training whistles in different colors for easy replacement, even if one is lost, the other has the same frequency. Made of plastic, they are durable, will not rust and are easy to clean. PET TRAININGThe whistle can help you train your dog to perform different commands, such as stand up, stretch, shake hands, squat, lie down. Please keep your whistle commands consistent and reward your dog with treats when he gets it right. FOR RECALLProper training will help with recall of responses and correction and positive reinforcement of the dog's behavior. It is recommended to start training at 8 weeks old, it will not harm your puppy's hearing. DOG WHISTLEOur dog recall whistle is tuned to ultrasonic frequencies and tones that are inaudible to human ears, you can hear some sound but not loud so it won't disturb your surroundings. But it allows your dog to always receive clear signals and commands in noisy environments. WITH KEYRINGThe dog training whistle has a key ring, you can connect it to the keychain, and the school bag will be lanyard for easy carrying and in case of loss. It requires multiple training for your dog to listen to your commands, Please be patient. Specifications: Material: ABS Type A Color: Black, white (1 each) Typw B Color: Light blue, light green (1 each) Size: (Approx)(LxW) 7.95x1.35cm/3.13x0.53inch Type: A, B Package Included: 2pcs x Dog Whistles Note: 1. Due to the light and screen difference, the item's color may be slightly different from the pictures. 2. Please allow 0.5-2 cm differences due to manual measurement.