Simply open this up and drop in any 9V battery you prefer or have lying around to use up and hey presto, you've got 9V's of isolated power that can be turned on and off!
Popular for additional power on boards and or Fuzz pedals.
This is the last of those that were shined up by Practical Patch's neighbour in lockdown 2020. Batteries not included!
Note: please when removing or adding batter hold fast the batter clip and break away from battery with care, any sudden nudge or pool could snap away battery clip wires from switch etc - thankfully this has yet to happen!