Poseidon Lever with Rectangular Rose, Emtek 5052POS

Passage – Always unlatches from both sides. No locking. For hallways and closets.

Privacy – Locks from inside with push-button or thumbturn. No key. For bathrooms and bedrooms.

Entry / Keyed – Key from outside, thumbturn from inside. For exterior and security doors.

Keyed Both Sides – Key required on both sides. For doors with glass near the lock.

Dummy – Non-functional pull, no latch or lock. For inactive panels and decorative use.

Storeroom – Always locked outside (key required), always free inside. For commercial storage.

Classroom – Outside locked or unlocked by key only; inside always free. For school and office doors.

Measure from the edge of door to the center of the bore hole or the lock body that you are replacing. Most backsets are either 2-3/8" or 2-3/4". 

To determine the handing of a door lock, stand outside the room or building facing the door. 

If the hinges are on the left side of the door, the door is Left Hand (LH).

If the hinges are on the right side, the door is Right Hand (RH).