C43910 -AF,  Includes C31249, C26670 OEM 12 voltage rectifier/regulator for all 200/400/600 series tractors with alternator/stater charging systems. This kit includes the highly recommend ground wire and replacement black male plug for tractors wiring harness if needs to be replaced or the plug us used for conversion from older stye regulators/rectifiers to this new style.
 
OPTION- Switch to quality aftermarket rectifier and save money!
On most models, this is located behind the access panel of the dash tower, held on with one bolt. This also replaces the two-bolt finned style larger regulators located behind the dash near the battery with some connection modification. This is mounted with one bolt through the center, it is highly recommended to run a wire from this mounting bolt directly to a good ground.