This is a custom battery holder for use with a Minelab Sovereign GT metal detector. It fits the AA battery pack lid cover and allows the use of a lithium polymer (lipo) battery which charges faster, makes the machine lighter, lasts longer than the standard nimh battery pack, can be recharged instead of just thrown away, etc. Many benefits to this type of battery. This is designed to fit a Turnigy 11.1v 1450mah lipo perfectly. You MUST use a proper lipo compatible charger to charge this sort of battery. You can just remove the contacts from the original AA battery pack and use either the futaba or JST type connectors plugged into a female connector and all soldered together. Some warnings: Make sure to observe polarity or you will fry your machine. Do not short circuit a lipo or it will go nuclear. Do not get a lipo wet.You may need to turn the print 90 degrees depending on the size of your print bed. Heated bed recommended. Print it out, remove original wires and contact points from bottom piece of original tray. Connect a female futaba or JST compatible connector. Solder together. Job done.