Thought I'd see if anyone would be interested in one of these old, from the "60s, automatic nut drivers. $20shipped, Sm flat rate box [it's heavy], PPal gift.
I have one of those under the John Deere brand. Exact same color and everything. Weird tool, as it doesn't have a very big range. But it does work as intended.
Small is 1/4, wide open is 7/16, let me check though, if different I'll repost.
Checked it out & it could go 7/32 on small side, although I didn't have a nut in the bin to try for sure. Had to open it a hair for 1/4. Wide open is 7/16. I'd guess it'd do metric too since the chuck hits the flange of the hex.