Review on Bluetooth Key Finder and Phone Tracker for Android/iOS - Anti-Lost Locator Device with One Touch Find - NUT Item Tracker for Keys, Backpack, Phone, Wallet - Improved Version 1 by Sourn Debremarkos

I really don't know how long the battery will last as I just got it. But at least a spare battery is included! I clip mine to my car keys - it's VERY light and thin. I was concerned about adding weight to the keychain that goes in my car's ignition, but this nut was light enough that I wasn't concerned about it. The sound is really loud and not terrible so I wouldn't mind listening to it for a minute while I'm finding my keys. It also comes with a small connecting cord as an alternative way to connect it to items. Overall I'm very happy with the gift and am considering buying two more for my house keys and wallet! lose what? lol)