Monkey Fist Self Defence Keychain - Neon Green Large Monkey Fist w/ Keyring- Neon Green. Used as a self defense tool, looks like a small bunched fist. Tied at the end of the string. Inside the knot is a metal ball making it easy to throw. String is designed to be extended or shortened for your own desired length. Convenient to carry as a keychain. Specifications: Ball weight: 3oz.