This "early-type" spider gear fits Hewland Mk-series open differentials made prior to 1999. Two required per differential. Uses Dished Washer for Spider Gear (Part No. 1410-B18), sold separately. Gears sold individually.
This early design is smaller in diameter than the later style. Both styles have 10 gear teeth. The washer bearing surface on this early type measures 1 3/8" OD, and the maximum OD (measured across opposite teeth) is 1.94". The later style is about 3/16" larger.