A more powerful standard engine and revised styling are 2006 updates of note to Volkswagen's retro-styled cars. New Beetles come as 2-dr hatchbacks or convertibles. A 150-hp 2.5-liter 5-cyl is now the standard engine. The 115-hp and 150-hp turbocharged 4-cyl engines are dropped. Available only as a hatchback is the TDI model with a 100-hp 4-cyl turbodiesel. A 5-speed manual transmission is standard. A 6-speed automatic transmission with manual shift gate is optional. Every New Beetle includes antilock 4-wheel disc brakes and front side airbags with head and torso protection. An antiskid system and traction control are standard. Audio systems have a jack for connecting digital music players. Also optional are leather upholstery and heated front seats. Convertibles have a manual-folding top or optional power top, and include a heated glass rear window and rollover bars that deploy if sensors detect an imminent tip.