A drive member selection mechanism is described, including at least one drive member and at least two selector members, wherein the drive member includes a first and second face, and further includes, on each face, at least one projection, and the selector members include, on at least one face thereof, at least one complementary projection arranged to selectively engage with a projection of a drive member, the arrangement being such that the projection(s) of a selector member and the projection(s) of the first face of a drive member may be drivingly engaged in a first torque connection and the projection(s) of a selector member and the projection(s) of the second face of a drive member may be drivingly engaged in a second torque connection, wherein the second torque connection is opposed to the first torque connection.