No soldering is required to install this handy rebuild kit. The Ni-Cad battery pack, charging jack, switch, and lamp socket are pre-wired and ready to install. You'll need an allen wrench to open the case, small philips screwdriver to remove the switch and bulb, and needle nose pliers to remove the charging jack. Note that the charging jack has a small pin in the center for use ONLY with the Color Viewer II. If your charging jack looks like a miniature earphone jack you have a Color Viewer Model I and need the corresponding battery pack.