I put mine on my bike keys, house keys, and water bottle, plus one inside my bike. The ones attached to things all have cheap silicone water resistant cases on S hooks to attach to the key rings and the handle to my water bottle. I got a 4 pack on Amazon for like $10. I dropped one down the center column of my bike bc it wouldn’t come out easy (you’d have to take much of the bike apart and then figure out how to remove it). My husband has one on a key ring and then a wallet with a built in AirTag holder. I lost a bike key and left my water bottle at a store (ended up getting it back the next day) and decided I needed them on everything important I bring everywhere.