A battery snap works with effects that run on a 9V battery but does not have a separate power jack. These effects include vintage pedals, wah's, and even some modern fuzz-pedals.
On the other end of the cable, you will find a standard 2.1 mm power adapter.
Length 46 cm.
Very tight connection, even more, proof connection than standard power jack.ᅠ
Safes space in tight pedalboard designs.
Even if your pedal would have a power jack, you can still file a small notch in the pedal chassis, string cable through it, and use this adapter. You can gain valuable cents by this method. ᅠ