Its a pulley instead of the air con pump I would say. I am considering putting a used pump on in place of the pulley. The original bolts were from factory fitting. Im not sure if the stealership robbed my alternator when new. Covid times ! Possibly they took my pulley of & never fitted correctly. I may have over tightened the replacement bolts. I now have a bigger problem ,getting the broken bit out of the block. The battery is now flat and not sure about connecting charger to battery when it is still connected.