A high frequency is available for this dog training whistle, with a crisp, loud sound that attracts your pet's notice. With smooth edges, this polished dog training whistle is safe to use without hurting your mouth. This dog training whistle is constructed of stainless steel material. There are 2 colors to choose from. This dog training whistle is suitable for outdoor use. Item Name: Dog Training Whistle Material: Stainless Steel Features: Ultrasonic, High Frequency, Wear-resistant Size Details: Black, Diameter: 1cm/0.39", Length: 9cm/3.54"(Approx.) Silver, Diameter: 0.7cm/0.28", Length: 5.3cm/2.09"(Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Dog Training Whistle