Lehigh County Auto Theft and Insurance Fraud Task Force has scheduled a free vehicle identification number etching event 9 a.m.-2 p.m. May 17 at the Whitehall Township Municipal Building, 3219 MacArthur Road.

The event is open to all vehicle owners in the Lehigh Valley and there is no limit on the number of vehicles motorists may bring .

VIN etching is the process of chemically etching a vehicle's unique identification number on all windows and sunroofs. The process does not harm the windows and doesn't detract from the vehicle's appearance.

Detectives who do the VIN engraving, which takes minutes, use special software and a dot matrix printer to create stencils with the identification number on them.

The stencils then are applied to each of the vehicle's windows and are dabbed with an acid solution. The stencils are removed and the glass is cleaned with glass cleaner. The number remains behind and is lightly etched into the glass.