by WOT » 13 Jan 2009 20:10
I wouldn't really call the Everest high security. It just has a check pin.
Everest is patented, however the C series blanks (C123, C145, etc) are open. Schlage sings consistent quality as a selling point, because they have total control over quality.
The C series blanks are open distribution, so it is illegal to make aftermarket blanks, but the OEM blanks are available to anyone. This just ensures they have the sole market over blanks. Their claim is true to a degree though. OEM Schlage blanks are made of nickel silver, even SC1s. The patented Everest ensures cheap, lower durability brass blanks don't get in the hands of customers.
The D series don't work any differently. Simply, the keyways are different and they're still protected under the same patent as the C series against third party manufacturing, butSchlage Lock Co. chose to designate as restricted and sell the blanks to authorized buyers.