Multipurpose tool the blackroll block is a multipurpose tool wich has an open flipside in which you can practically store your blackrollreg mini or blackrollreg duoball amp ball sold separately the blackroll block can be used as self myofascial release tool the blackrollreg block serves as a higher deck for pinpoint massage using a blackrollreg duoball or blackrollreg ball 8 cm or blackrollreg mini calvesachilles targeting muscle groups that are otherwise hard to reach