I made adapters for both the Bandai Action Base 5, action base made by soozafone and other third party knock off bases.

The difference between the two action base adapters is one is meant to sit like and “L” and the other and upside down “L”.

 

I would recommend printing in a stronger material such as PETG as you don't want the begs getting stuck in the bookshelf when the adapter is being removed.