a $5,000 Prowler trailer option was available from Chrysler dealers. These trailers resembled the back end of a Prowler and had smaller versions of the five-spoke wheels found on the car. They could be ordered to match a car's factory color. The cars were equipped with a trailer hitch to accommodate the trailer option, however, a warning was affixed to the hitch that indicated that the trailer hitch was not to be used to tow any other accessory (boats, recreational vehicles (R/V's), campers, etc.) other than the accessory trailer. By doing so, the factory warranty would be considered void. Legacy Other retro-styled vehicles followed the Prowler, including the Chrysler PT Cruiser, Chevrolet's SSR, HHR, and the 2010 Camaro, Ford's 2002 Thunderbird and 2005 Mustang, 1999 Jaguar S-Type, 1995 and 2004 Jaguar XJ, 2002 Jaguar X-Type, as well as the 2008 Dodge Challenger. In 1998, a Plymouth Prowler was sealed in a mausoleum as a time capsule in Tulsa, Oklahoma. While similar in concept to the buried 1957 Plymouth Belvedere that formerly resided near the courthouse, the buried Prowler was sealed in Centennial Park in an above-ground vault and sealed within a plastic box instead of plastic sheets that covered the Belvedere. Experts believe the Prowler has a better chance of looking how it did when it was sealed when the time capsule is opened in 2048 when it will be returned to Chrysler. In 1999 at the Specialty Equipment Market Association's annual car show in Las Vegas, Nevada, Chrysler unveiled the Plymouth Howler concept. Inspired by hot rod trucks, and based on the Prowler, the Howler featured a small, truck-like bed with a tailgate and hard tonneau cover. Under the hood, an adapted version of Jeep's new 4.7 L PowerTech V8 engine replaced the production model's 3.5 L V6. A Borg-Warner five-speed manual replaced the production four-speed automatic. In 2004, Chrysler introduced the Chrysler PT Cruiser Convertible, which was a two-door, four-passenger version of its popular PT Cruiser Wagon with a shorter roofline and a power-retractable soft convertible roof. The PT Cruiser Convertible went on sale in the spring of 2004 as early 2005 model year vehicle. The car was restyled with slightly revised exterior styling and a new interior in 2006 and then was subsequently discontinued after the 2008 model year (The PT Cruiser (Wagon) itself was discontinued entirely in 2010). Chrysler Corporation hosted a 10th-anniversary celebration on August