The Federal Trade Commission includes VIN etching on a list of upsold services including extended warranties, service and maintenance plans, payment programs, guaranteed automobile or asset protection, emergency road service, and other theft protection devices, and warns consumers about the practice of upselling when buying a vehicle.
[1] VIN etching uses a variety of methods, commonly a stencil and an acidic etching paste, to engrave a vehicle's vehicle identification number (VIN) onto the windshield and windows.
[2] VIN etching can also increase the odds of recovery of a stolen car by police.
[3] VIN etching is recommended by police departments, insurance agencies, and government automobile/vehicle theft prevention agencies[4][5] This service is sometimes offered free of charge at sponsored events.
[6][7][8][9][10][11][12] Vehicles with VIN-etched windows may be eligible for insurance rate reductions of as much as 15% in some US states.