Ferrari Part Number 138391, REAR CRANK SEAL 100/120/13 HALF METAL 12CYL shown here as used in 250 SWB Table 3 Crankshaft, Rods & Pistons. Location in Diagram: 4. Required Quantity: 1. This Ferrari part is used in more than one diagram. Click on the diagrams below to see alternative uses of this part: