Mercury Quicksilver OEM Belt tensioner for Verado 135-300 HP 885349t05 8M0101707
It's part of the alternator belt system, maintaining proper belt tension to ensure efficient charging and drive-belt operation. 350SCi Verado - 1B716557 THRU 2B143542. 135 VERADO (4-STROKE)(4 CYL.). - 0P419487 THRU 0P464487.