Rocktron Unity Tuner - Manual (Page 15)

How to change the battery:
To change the battery, turn the pedal over and remove
the 4 screws on the bottom. Remove the back cover.
Carefully remove the old battery and replace it with a
new 9V Alkaline battery. Replace battery in the same
area as the old battery was located. Place the back cover
on the pedal and re-insert the screws.
Save yourself tons of money in batteries by using the
Rocktron DC OnTap Universal Power Supply to power
this pedal (sold separately). The Rocktron DC OnTap
provides a constant flow of power to the pedal, unlike a
battery that will degrade over time. The Rocktron DC
OnTap Universal Power Supply can also power up to 20
pedals and can be used with both 110V and 220V power
sources.
Check, www.rocktron.com for more information on the
DC OnTap and where to purchase.