SMARTKEY
Smart key
A smart key is an electronic access and authorization system which is available as an option or standard in several cars. It was first developed by Siemens in the mid-1990s and introduced by Mercedes-Benz under the name "Keyless Go" in 1998 on the W220 S-Class following its design patent filed by Daimler-Benz on May 17, 1997.The above text is a snippet from Wikipedia: Smart key
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