Higher Durability. Featuring a more reliable casing attachment. TOOL ONLY!USER BENEFITS:Lithium-ion batteries have greater life spans than their Ni-MH or Ni-Cad counterparts giving 430% greater run time.Lithium-ion?s 40% weight saving means 18 volt power can be obtained by a battery that weighs the same as a 12 volt Ni-MH battery.Anti-tilt device to prevent screws from swaying.Dust proof construction.Foldable screw guide that keeps the screw strip tangle free.Silent clutch.Battery and Charger sold separately.