In Order to make sure you get the right item, please confirm your OEM NUMBERS match up with one of the Numbers in our description Application For Chevrolet Silverado Suburban 1500 1999-2002 For GMC Sierra 1500 2001 For GMC C1500 1996 1997 1998 For GMC K1500 1997 1998 For Chevrolet Tahoe 1996-2000 For Chevrolet K1500 1996 1997 Position: Upstream & Downstream OE/OEM Number: 9617178, 234-4012, SG454, SG236, 13474, 234-4018 Package Include: 4pcs Upstream & Downstream Oxygen Sensor O2 （2 Front+ 2 Rear） Advantage - Condition: Brand New - warranty: 2 years warranty for any manufacture defect - best price,top quality - deliver quickly - Designed for comfortable use and best quality - Replacement of the original item (safety, accuracy, service life and quality) - High-quality materials for high durability and long service life Notice -Instruction Ne sont pas inclus. installation professionnelle est recommandée -Contactez nous s'il vous pla?t pour tout ce que nous pouvons vous aider