I purchased 10 packs of these locks and had such a difficult time installing them that they are now sitting on my shelf as multiple "shelf racks".I paid ~ $14 for each of these locks and they are not standard. The other writer was correct. The part that you install on the inside of the hole is longer than that of kwikset, schlage and other standardized locks.I did not have a drill or a tool to increase the depth of my existing circle for the hole and as a result, could not get the piece to fit.I spent almost an hour trying to install one lock and I can normally install a quickset or other lock in about 6 to 10 minutes.I am dissapointed and do believe in the old saying that "YOU GET WHAT YOU PAY FOR". What I got was a waste of my money.*******Right now they are retailing for $29.99 and they are not worth the $14 that I paid for them.Thanks Amazon for letting me share my opinion.