This is a Kyosho America EZ007 Rear Hub Carrier Set (SAND MASTER)
Kyosho indicates this will work with:
EZ Series SANDMASTER (Black) 1/10 EP 2WD Buggy KIT KYO30832T4
EZ Series SANDMASTER (Purple) 1/10 EP 2WD Buggy Readyset RTR KYO30831T6
It was added to our catalog on Monday July 15, 2019