U-Joints connect rigid (drive shaft) rods whose axes are inclined at an angle to each other, and are commonly used in shafts that transmit rotary motion.
Sierra 18-2104 Heavy Duty U-Joint Rockwell style – includes both straight and 90 degree grease fittings.
Fits all Mercruiser MR-1 and Alpha-1 units - Serial Number 1684188 thru B418818 (Approximate years 1978 thru 1990)
Also fits all Mercruiser TR, TRS, and II SSM outdrives.
Replaces Mercruiser 75832A2, 75832T, OMC Cobra Drives (1986 thru 1989) 912214, 915716, Volvo-Penta AQ200, 250, 270, 280 and 290 Sterndrives.