here is a link to it
http://www.440source.com/flywheels.htm
they work with smallblocks as long as your motor is zero (internal) balanced...for 99 bucks and being billet steel, it sure as heck beats getting a stock one resurfaced, and the extra security for your feet is worth it...oh and they are balanced when you get them...i double checked mine to be sure and sure enough it was
good luck!