Professional™ Alternator (335-1212) by ACDelco®. Current: 140 Amp. With 8 Groove Serpentine Pulley. Pulley Size: 69.1 mm. With Internal Fan. Plug Position: 11:00 O’Clock. Voltage Regulator: Internal. Rotation: Clockwise. Thoroughly tested and backed by competitive warranty coverage, ACDelco Professional NEW Alternators – for GM and non-GM vehicles – are manufactured using ISO Quality Standards. ACDelco Professional NEW Alternators use 100% new components. Finished units are 100% end-of-line-computer-controlled tested to ensure proper functionality, fit and long-term reliability. They feature a 2-year/Unlimited Mile Limited Warranty and are available for popular volume applications on the road today.