Makita BFR550Z 18v Auto Feed Screwdriver FEATURES 22 minute charge time with the air cooled Makstar Optimum Charging System. 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 SPECIFICATION Battery TypeLithium-ion  Charging Time   22 min Body only machine  Voltage   18 v Drywall screw   55 mm Max dry wall screw   4mm x 55mm  Screw Size Range   25 to 55 mm Noise sound pressure78 dB(A) Noise K factor3 dB(A) No Load Speed   4000 rpm Vibration K factor1.5 m/sec² Vibration no load2.5 m/sec² Net weight2.3 kg