Making its debut for 2006, this five-passenger compact wagon was named for its "Heritage, High Roof." Styling was inspired by the 1949 Chevrolet Suburban. Sharing its underskin architecture with Chevrolet's Cobalt compact car, HHR came only with front-wheel drive. LS and LT models were offered, both with a one-piece rear liftgate. The base engine was a 143-horsepower, 2.2-liter four-cylinder. Optional on the LT was a 172-horsepower 2.4-liter four. Available with either engine was a five-speed manual transmission or a four-speed automatic. Included with the automatic was a remote engine start feature. All HHRs had air conditioning, power windows/locks/mirrors, remote keyless entry, split folding rear seat, and a fold-flat front-passenger seat that could allow carrying longer items. LT editions added a power driver's seat, upgraded trim, and alloy wheels. The LTs were available with a 2LT package that included the 2.4 engine, sport suspension, and 17-inch wheels versus the standard 16-inchers. Antilock brakes were part of the 2LT package, and also were a standalone option. When ordered with an automatic transmission, they included traction control. Head-protecting curtain side airbags, OnStar Assistance, and satellite radio were available but not standard. Chevrolet's HHR competed mainly against the Chrysler PT Cruiser, which also featured retro styling. Additional rivals included the Pontiac Vibe/Toyota Matrix duo.