Unlike conventional variants that are cut with specific grooves and notches to open a particular lock, modern vehicles come equipped with a transponder key. In addition to the mechanical complexity of the key blade, these keys contain transponder car key chips that need to be programmed to the exact configuration in order to fire up the engine. This adds a layer of complexity to the duplication process and cuts down the possibility of car theft. Another variant, GM vat keys, contains a resistor chip that needs to carry the precise value to allow the vehicle to start.
