Keep this running with 1 hand. When you are fully focused on thinking tasks, you can use Keychain Spinner to improve your attention and concentration.
Keychain, Key Chain Spinner Toy, for Ninja Spinner Keychain, Spinning Keychain Toys for Keys, Gifts for Kids And Men(2pc).
Ninja Keychain
Ninja Keychain Fidget Spinner
Ninja Keychain
The Ninja Keychain Spinner
Keychain for sale - New and Used - OfferUp
Keychain for sale - New and Used - OfferUp
The Ninja Keychain Spinner
Ninja Keychain