The ND-generation Mazda MX-5 Miata is lighter and smaller than the previous generation, bucking trends of vehicles growing in size as years progress. A 2-liter engine produces 151hp in the early models, while in 2018 the engine was tweaked to produce 181hp. Apart from the standard convertible body style, a semi-convertible known as the RF model (Retractable Fastback) was revealed in 2017 using a power-folding targa-style top and powered rear glass window to give open air motoring with more security than a soft top.