Ding King

The pitch: "Just turn the wing nut and watch that awful dent just disappear!"

April 2009. The Ding King Twist-A-Dent tool is another product promoted by TV pitchman Billy Mays. In the television infomercial, Mays pounds a car hood with a rubber mallet, and then uses the Ding King to remove the resulting dent. "It's like dialing the dent away!" Mays says.

When a leading consumer magazine tests the Ding King and a competitor on dozens of dents, panelists report improvement 80 percent of the time. Consumers also report success with the Ding King -- at least some of the time.

In other instances, users and experts say the Ding King Twist-A-Dent does nothing. According to reviews, it seems to work best on shallow, uncreased dents that are no bigger than 6 inches in diameter and aren't near the edge of a body panel. Users say it alleviates some bigger dents, but it may leave ripples or small dents in the metal. Some say it takes hours worth of repeated tries to remove a dent.

Occasionally, users who buy the Ding King say the tool's bonding agent damages their paint. (One admits he didn't notice the warning that Ding King should only be used on factory paint.) However, expert testers do not experience any paint damage, leading them to conclude that it's worth a try, considering you could pay $50 to $200 or more to have a dent removed professionally.

Consumer Reports conducts a definitive test, trying Ding King and a competitor on dozens of dents. Unlike most Consumer Reports content, this report is free. KDKA, a TV station in Pittsburgh, also conducts an expert Ding King test with the help of a professional auto body repairman. User reviews at Amazon.com, InfomercialRatings.com and Epinions.com show the same pattern: The Ding King works on some dents, but not all.