My concern with the older Sovereigns rechargeable packs are getting harder to find and expensive.Yea there is a sight that you can get these packs for over $30.00,but with the price of rechargeable AA batteries it may be better to make your own pack.Anyway the AA rechargeable batteries Blue babies 2600s(actual yellow batteries) 16 for .01 off of Ebay LOL shipping from Hong Kong $12.98 still not bad.I used white duct tape, solder,wire,and a female connector.Ten of these 2600s 1.2V should keep my battery pack in specs.I soldered the ends together and used wire to solder the bridges.After the connector wires were soldered I wrapped in duct just one layer.Before I added the connector itself I checked the battery pack with the ohm meter which was dead.My thought this is what happens when you pay .01 for 16 rechargeable AA batteries.After the pack was wrapped and the connector added the pack was charged overnight.OK now for the drum ro------ll the pack was plug in and the Sovereign fired up.The next stage is in the field to see how long this pack will last,which a break in the weather is needed for field use.