Granco / Granco Industries Inc., 4009 E. 138th St., P.O. Box 171, Grandview, MO 64030-0171 / phone: (816) 966 9400 email:
[email protected] / contract supplier for military /
https://www.garagejournal.com/forum/threads/granco-tools.14174/

Granco Industries NSN 5120-01-116-6047 23-pc 1/2" drive metric socket set

Granco Industries NSN 5120-01-116-6047 23-pc 1/2" drive metric socket set
This is a Granco NOS 23-piece 1/2" drive Metric 12-point socket set - sizes run from 10mm to 32mm (no skips)
Came across this set yesterday searching for some drift punches and gave these to my buddy (who will most likely be using them to do some work on a couple trucks here.) I found an NOS Indestro set that I like more.
It would appear from comments above that Granco was still offering products and a catalog as late as 2008, but discontinued their socket line in 2009.
Notwithstanding the comments above by 06blueram (see posts #16 and #20), I cannot help but notice the resemblance to sockets sold by other military contract suppliers, specificially JS Technology, ProAmerica, and Thorsen. (see second photo image.)
There is no question that Granco was outsourcing at least part of their product line:

Granco 11650 4-in adjustable wrench
(photos ebay)
The odd wrenches, however, seem to have been made in house:

Granco 16130 9/16" flare nut/box end wrench
(photo ebay)
Pure conjecture and speculation on my part, but it sure looks to me like Granco was stamping out some very specialized wrenches and torque adapters for the military, but outsourcing sockets (perhaps from National Hand Tools out of Dallas?) and (obviously) their adjustable wrenches from Western Forge. Just my lousy opinion, of course.