Proxxon PS 13, 12 Volt Pen Sander #28594
If the other sanders are detail sanders, than I’d have to call this one a fine detail sander. This tool is designed to run off of 12 VDC, from a 1.0 A or larger Micromot transformer so don’t think you can just buy it and plug it in. Check their website to make sure you’ve got everything on hand you’ll need.
The truly great thing about this is that it’s a pencil sander with eight different pads. That’s four straight ones and four angled ones, in a variety of shapes. These can get into places that the other detail sanders I’ve mentioned can’t even think of thus allowing this sander to be used for shaping, finishing carvings, and may other truly detailed jobs with irregular surfaces.