These 'Tamashii Stage Dragon Ball' stands were released exclusively at events in 2019 (such as SDCC). They consist of a total of 7 official stands for your S.H. Figuarts figures, each with a base shaped, colored, and designed to resemble a Dragon Ball. Since there are seven, each stand features between one and seven stars.
This 'Tamashii Stage Dragon Ball' accessory is a pack of 7 stands for your articulated S.H. Figuarts figures, released as an 'Event Exclusive Color Edition' for events like SDCC or NYCC in 2019.
It is the first separately sold accessory that the brand has dedicated exclusively to Dragon Ball, and since they are stands, they were released as a pack of 7, each representing one of the seven Dragon Balls. They have a matte color, although the plastic is translucent.
The following year, also as an Event Exclusive release, the pack was reissued, but this time with a metallic recolor instead of a matte finish.
As for the clamp, it’s a standard support type used in Tamashii releases.
According to listacompletade.com, this accessory is only recommended if you're a hardcore fan, as its price is exorbitant and it serves the same function as the regular stands.
Here you will see some of the more than 200 S.H. Figuarts releases that Tamashii Nations has brought us from Dragon Ball.