I purchased this safe to replace a twenty one year old Sentry Safe.  The older safe battery cartridge was not making contact due to a worn connector when I dialed in the combination.  The new safe has a much improved battery cartridge that eliminates this problem. Since my old safe is the same size as this one I was able to re use the shelves for the new safe.  I also like the fact that it is water resistant and has a LED light for the interior.  Overall the quality of Sentry safes is outstanding.