Lock set components:  It is easier to discuss your lockset requirements when we all use the same names for the same parts of the lock set.  Please open this word document to see what terms we use. 

Door Handing - Is my door Left hand or Right Hand? - Our simple explanation is that you should stand on whatever side of the door you need to so that you can see the hinge pin or the butte of the hinge.  If the hinge is on the left - it is a left hand door.  If the hinge is on the right - it is a right hand door.  Please verify the handing using the diagrams below - click on the appropriate image to enlarge.:

For mortise locks (swinging doors):

For rim locks (surface mounted):

For sliding doors with privacy locks:

Replacing A Lock - what do I need to look at? First check your door thickness and determine which of locks will suit that thickness. (Less than 1" Rim Locks, 1" and larger 4040 series, 1 3/8" and larger 3200 series).  Compare dimensions for the faceplate (click here to see what a faceplate is), backset (distance from edge of door to center of handle) and centers (distance from center of handle to center of keyhole). Next determine what function you want: Passage only (usually for closets, passageway doors), Locking (either with skeleton/bit key or cylinder with key outside, thumbturn inside - for exterior doors, stateroom doors, etc.) or Privacy (thumbturn inside, emergency access outside - for head doors or staterooms). Finally determine the finish: polished brass, polished chrome or matte/satin chrome.  Or, get as many dimensions as you can, contact us and we'll suggest what lockset we think will work best for you.