Outboard starters serve as generators function similarly to the starter motor of a standard riding lawnmower. This starting motor does not use a Bendix and has a driving gear constantly in contact with the starter ring. When you apply power to the starting motor, it rotates the engine until it revs. It then brushes and activates the wire inside. Starters take on the characteristics of an alternator or generator, sending electricity back to the charging batteries. In addition, an onboard regulator turns on and off the charging element within the starter to protect overcharging the boat's battery. Key Features: Suitable in marine applications Highly resistant to vibration Resistance to corrosion Features a driving gear with ten teeth Epoxy powder coating for enhanced corrosion resistance Motor shafts induction cases with hardened bearing surfaces for an increased wear resistance Specifications: Brand: Acro Marine SKU: 5385 UPC: 693006005430 Weight: 7.00 lbs Manufacturer Part Number (MPN): 5385 Fits: Mercury 35-40 hp, 2-cyl Replaces products: 57-5385, 693006005430, 50-41583, 50-898265-007, 50-41583T, 50-898265007 10-tooth drive gear. Fits: Mercury 35-40 hp, 2-cyl