The "GM" is a mass-produced machine that is "simplified and standardized" based on the Gundam.
This machine was designed for the technologically inferior Earth Federation Forces to attempt a counterattack through quantity tactics.
I purchased this machine and the HG Rick Dom at the Gundam Base Satellite in Sendai.
On that day, November 7th, my "top priority" was to "prove I had visited Gundam Base," so I stayed overnight at a ryokan in Bandai Atami, which was my base at the time, and the limited express ticket for my round trip on the Tohoku Shinkansen "Yamabiko" from Koriyama Station cost more than the cost of the machine itself.
After all, it was the first time I had ridden in the "Green Car & Gran Class" on the E5 Series Shinkansen in years.

[G-type Workshop] HG Gym | 越後浪人's Gunpla works