It is here to save you $400.00 per printer! Developed for Oki C5000 series printers, and extensively tested on many actual C5100/5150/5200/5300/5400n, C3200n series printers This is for one kit, you will install in any color drum unit: Yellow 42126658, Magenta 42126659, Cyan 42126660 or Black 42126661 It is 100% compatible with any drum cartridge you have in your Okidata C5100, C5150, C5200, C5300, C5400, C3200, C3200n printers. Please note: pictured drum not included - reset kit only for drum as on picture! Sorry we can't display this part on picture! Spend 5 minutes and get 25%-100% more life out of used drum you already have ! Free tech support by e-mail ! These kits easy to install in just 5 minutes each - no special tools required, illustrated instructions included. Please note: used drum you have must be in good working condition prior message "order drum" or "replace drum" appeared. What feedback my buyers posted? "WOW this product works!! I'll keep buying from thiser!!!" Worked BETTER than expected!! Will definitely use again! Thanks A+++ I Thank You for saving me so much money, Will return! Thanks! I'll be buying more in the future. Thanks for reading!