Abstract: A battery powered banding tool is adapted with a punch for use in tightening and securing center punch type band clamps. A hand-held electrically powered drill is configured for rotationally driving a band tensioner mounted thereto. The band tensioner includes a gear box, and a mount including a generally U-shaped rigid strap which engages the rear of the driving tool to secure the gear box. The gear box contains a worm gear axially coupled to the chuck for powered driven rotation thereby. The worm gear is in intermeshing relation with a winder gear disposed within the gear box and configured for rotation about an axis disposed generally perpendicular to the worm gear axis. A winder, defining a band-receiving slot, is affixed to the winder gear and rotationally driven thereby. A punch assembly, defining a band-receiving slot, is disposed in forwardly spaced aligned relation with the winder.