Transponder Keys
There is no visual difference between metal keys with plastic head and Transponder keys. If car owner was not told, in the time of purchase if his/her car is equipted with Transponder equipment, will be impossible to determine that later ( some Chrysler keys are colored gray and that is the only difference). It is smart to ask your dealer abotu your vehicle transponder status. That will save some aggravation and money if keys are lost and locksmith called.
Do not mistake GM VATS keys. They are very simmilar to transponders as they have some kind of electronic unit on the key blade ( resistor). They are easier to "program" and there is no need for special equipment.