Battery World designs and manufactures custom battery packs and assemblies for any portable applications as well as stationary back-up power. (Ni-Cd or Ni-MH). The re-building of your battery pack includes the complete replacement of all the rechargeable cells, with factory fresh matched cells that are of greater quality and capacity than the original equipment. This will result in performance that exceeds the original battery pack. If your drill (or other piece of equipment) is 5 years old it is likely that the replacement packs are also 5 years old. They stopped making the battery packs when they switched to the new model. There has been considerable improvement in the quality and capacity of new cells and they continue to improve every day.