The Quack Hammer is a melee item, much like the Thunder Stick. Upon using the Quack Hammer, the user will proceed to swing it around for about 5 seconds, dealing damage to any other racers who draw near and causing them to lose speed.
A variant of the Quack Hammer known as the Quack Hammer+ exists exclusively in Mario Kart Arcade GP. This variant extends the duration of the attack by around 2 seconds.
The Quack Hammer is one of two melee items to have a unique sound when in use - it plays a squeak sound every time it is swung. The other item is the Stretch Punch.
The Quack Hammer's appearance differs depending on which character it belongs to - Pac-Man's Quack Hammer is red and bears a Pac-Man logo, while Ms. Pac-Man's Quack Hammer is pink and bears a Ms. Pac-Man logo.