Woodruff Key (Old Style)
Replacement Woodruff Key, old style for 2002-2006 T1N Sprinters.
Unfortunately, the only way to really know what Woodruff Key you have is to take the Harmonic Balancer off. There are two styles: the half moon keyway, and this straight-away style keyway.
The straight away style keyways require the front timing cover to be torn down to replace, as this keeps the crankshaft in time with the oil pump.