TC Electronics polytune. Excellent condition, works great. Velcro on bottom. Only replaced it because I needed something to help me intonate my MTD with buzz feiten tuning system. $60 shipped to US lower 48 states.
You can use either a 9 volt battery or a standard 9v power supply. That screw head in the middle of the bottom of the pedal takes off the bottom plate to replace the battery if you choose that option. You can unscrew it with a pick of a coin.