Features: Suitable size for you to hang on the for key chain, lightweight and portable, providing more convenience for you in daily life. These for key finder tags are suitable for attaching to keys, pets, phone, wallet, handbag, kids' backpack and so on, and it also can be a nice snoring reminder, bring you nice using experience. Easy to apply: simply whistle and this tracker will flash and beep to help you, making it easier for you to find your items, button which located at the front of the transmitter allows you to turn on or off the flashlight easily. for Key finder product function: audio sensor whistle to find objects + LED flashing warning light function + power switch. How to use the for key finder: Turn on the side switch, when the whistle sound reaches 80 decibels, it will make a beeping sound. At the same for time, there is a red indicator light for searching. The product can be equipped with a flashlight function for lighting. for Key finder product accessories: The product comes with a 2.5CM for key chain aperture. Specifications: Thick: Approx.2cm/0.78inches Width:Approx.2.9cm/1.14inches Length:Approx.5.3cm/2.08inches Material:ABS Color:Red/Blue/Black/White Note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings. Package includes: 1 x Whistle for Key Finder