OK, I tried to find a DSPIAE sanding pen, and came up empty handed. HOWEVER, it is listed on the DSPIAE site as a "sharpening pen".

They've got it
listed as a sharpening pen, but
label it as a sanding pen. Crafty fellows, very trixie Hobbitses.
I've got a low-speed Dremel which I love, but I'd like something smaller, and this is it.
Thanks for making me/us aware Gary, and thanks to Berman for posting that chuck too.
Warren
PS: I've found that while most DSPIAE products are expensive, they are worth it. You get what you pay for. Your madness may vary.