Lock indicators useable to signal the locked or unlocked state of a lock at both sides of a door selectively secured by the lock. Lock indicators include a first cuff for receiving an input causing the first cuff to transition from a first position to a second position associated with the locked state and the unlocked state. The lock indicators include a second cuff for receiving input from the first cuff via a transmission rod causing the second cuff to transition from a first position to a second position associated with the locked state and the unlocked state.