This is the lock tab that sits under the crank pulley (or vibration dampener) in order to secure it in place.
NOTE: When installing our harmonic balancer pulley on a 948 or 1098 (available HERE) you will have to hammer the part of the lock tab that lines up with the machined flat groove in the mounting face of the pulley to index it and ensure the lock tab actually keeps the bolt from turning. This can be done using a punch and hammer striking in the area indicated in the picture.
If your crank pulley bolt is old, we recommend replacing it as well.
