This is an Adjustable 4-40 Ball Link Set with Hardware. Adjustable means you can adjust the tension on the ball.
1/4 in. wrench for the lock nuts, 3/32 in. allend wrench for the socket head cap screws, Small flat head screw driver for the small silver screws.
The ball link has a 1/4 in. hex to make it easier to install with a 1/4 in. open end wrench.