A meter assembly includes: a meter housing including a top portion, the top portion including a mounting boss, the mounting boss including an engagement hook and protruding axially from a top surface of the top portion of the first housing; a register housing connected to the top portion of the first housing and configured to rotate with respect to the first housing about a rotation axis; and a retaining fastener connecting the second housing to the first housing, the retaining fastener including a one of a hook and a flange configured to engage the mounting boss and a one of a hook and a flange configured to engage the second housing.