A controllable coupling assembly and a coupling member for use in the assembly are provided. The member includes a first coupling face oriented to face axially along a rotational axis and has a set of locking formations angularly-spaced about the axis. The member also includes a second coupling face having a reverse pocket which receives a reverse locking element. The pocket defines a first load-bearing surface adapted for abutting engagement with a load-bearing surface of the reverse locking element. The second coupling face is oriented to face radially with respect to the axis. Each of the set of locking formations defines a second load-bearing surface adapted for abutting engagement with a load-bearing surface of a forward locking element.