BMW Genuine Bolt for Drive Belt Tensioner Alternator A/C Power Steering for 128i 323i 325i 325xi 328i 328xi 330i 330xi 525i 525xi 528i 528xi 530i 530xi X3 28iX X3 3.0i X3 3.0si X5 3.0si Z4 3.0i Z4 3.0si Z4 30i BMW Genuine Bolt for Drive Belt Tensioner Alternator, A/C, Power Steering Belt . Manufacturer Warranty: 12 months / 12000 miles Please see Product Description below for compatible models.