Revolution Gear and Axle, Replacement series, Rear axle shaft for GM 8.5 Inch 88-91 Sub and FS Blazer 2WD, fits both Left and Right side, 31.5 Inch 30 Spline (OE#26010415 / Hollander# 447-1669). Revolution replacement series axles are made from 1541H Steel and utilize a state of the art computer controlled heat treated process. The use of better material and better heat treating process gives our replacement axles a 10 Percent increase over the OEM axles.