The B17-99D-2RS is a high-precision, single-row deep groove ball bearing specifically engineered to provide flawless rotational support in high-vibration and demanding mechanical systems. Distinct from standard metal-shielded options, this specialized unit features a double-sided nitrile rubber sealing system (2RS). This provides an impenetrable physical blockade against water, fine dust, and abrasive particles while trapping the high-performance internal grease. Manufactured to precise 17x52x17 mm dimensions, the B17-99D-2RS is universally recognized as a critical replacement component for automotive alternators, generators, and heavy-duty electric motors.