The Mazda MX-5 Miata Base Model for the NA generation was available for model years 1990 through 1997. As with the rest of the Miata range, the base model was powered by a 1.6-liter twincam four producing 116hp. From 1994 ownards, displacement was increased to 1.8-liters, now producing 128hp. Both manual and automatic transmissions where available. While differences exist for each market, in the US, the base model was available in multiple trim levels: an "A Package" offered power steering, a leather-wrapped steering wheel, aluminum alloy wheels and cassette stereo. The "B Package" added power windows, along with cruise control and headrest speakers, while the "C Package" included a tan interior and top with leather seats. The R-Package, commonly considered a separate version, was geared for performance. These packages are not to be confused with Mazda's Special Edition, Black Miata, Limited Edition, and M-Edition variants.