At first, a box Chevy on 20 inch wheels. More recently (2006) any older General Motors car on tall chrome wheels and preferably with outrageous candy color paint job, custom interior, big sound, and juiced up engine. A popular trend in the Southeast USA.
Hi-Risers have been appearing in numerous rap videos of late and are becoming the car of choice for the hood because of their bold colors and huge 'how the Hell did they make those fit?' chrome shoes.