Kusari Kusari no mi (chain-chain fruit)

Logia type fruit

Capability: You are able to create strong iron chain links for your body, they can be destroyed only be destroyed by sharp objects or large amounts of force. The chains can be controlled as long as the links are connected to your body however you can open up the chain link to let something in (for instance you could insert a blade into the end and then stab someone with it). Further more you can make two sizes of chains, one which has chains that are 3 inches in per link and is relatively thin and another that has long chain links that are 3 feet in length but travel much slower and are thus used for more of a defensive reason. The chains can travel within a 50 meter radius and the user can have up to 20 smalls chains active and up to 4 large chains active.

already exists; use this one
https://theonepiecerp.rpg-board.net/t2033-kusari-kusari-no-mi-the-chain-chain-fruit?highlight=kusari

... damnit

it is always better to look for an existing fruit than start a new one