Does it contain the necessary information such as coverage limits and VIN number of you vehicle? The troubling part is that the ad states that you must provide evidence of already having insurance on your vehicle.
Perhaps you should call your current car insurer and see what they think of this littler caper. if there's conflicts and coverage gaps between the two it's better to know about them now rather than find yourself in a wreck and both insurer's leave you standing there with your thumb up your bodily orifice.