HG 1/144 #114 Ball Twin Set [2010]

The Federation refitted about 1200 of the civilian-model worker space pods, known as SP-W03 Space Pods. The Federation reinforced it with heavier armor and mounted a 180mm low-recoil cannon on top. The Ball mobile pod also had vernier thrusters mounted all along the body.

Not one Ball, but two! The latest HGUC release from Bandai gives you two identical RB-79 Balls (EFSF Mass-Produced Mid-Range Support Mobile Pods), both with 180mm cannons or twin guns that you can switch in and out, and the arms are articulated as well. Also, Bandai has supplied two display stands so your Balls don't roll away.

Lore excerpt from gundam.fandom.com.