The TeraFlex TJ: NP231 Extreme Short Shaft Kit is what short-wheelbase TJ Wrangler/Unlimited owners have been dreaming about for decades. Not only does the Extreme Short Shaft Kit improve on strength, but it also increases driveshaft length by up to 7″ over a stock application. This kit is also more than 3″ shorter than a standard Slip Yoke Eliminator Kit and 1.5″ shorter than an ATLAS II. Speedometer readings are transferred through a tone ring and electronic sensor.