Adapter for connecting 2x ToolkitRC M7 chargers with a widely available Parkside 4ah batteriws (Lidl). Printed in PLA. Item sold without battery or charger.
 
I chose to use Lidl Parkside 4ah battery as a solution for this method of charging because the battery is cheap, have a built-in balance charger and deep discharge protection. A big supply chain spread through Europe provides easy access to batteries, which provides a backup when needed.