Abstract: The present disclosure relates to preventing rotation of a barrel lock when opened by a key. At least one example embodiment includes a rotationally actuated barrel lock for securing electric meter boxes and the like, and a spring loaded clip for mounting inside the meter box. Lock actuation is characterized by rotation of a key relative to the lock. The barrel lock includes a head portion, and a smaller diameter shank portion with flatted areas thereon. The clip includes, in at least one example, a lock receiving opening with internal protrusions which engage the flatted areas on the lock shank, thereby preventing rotation of the lock when it is engaged by the key.