This is an accessory or set of accessories for Gundam models.
A set of new armor parts, yet unnamed, from the upcoming second season of "Gundam Build Divers Re:Rise!" This set is to be used by the protagonist, and is part of the Core docking system, so it can be equipped with the Core Gundam II for new customization options!
The theme of this exterior parts set is "drill," as the parts offer the ability to build a massive drill weapon that takes the place of the Gundam's arm!