These were purchased for a 2009 Dodge Charger SXT All Wheel Drive, which has 4 CV axle shafts (and 1 tone ring per shaft). The immediate benefit was that this item is a 4 piece set, which offers a huge bonus for pricing, along with having to only order one part number! The tone rings are difficult to get to in the vehicle, which requires a lot of disassembly, but once apart, the new tone rings fit very nicely onto the existing CV axle shafts. Use a small dead blow hammer or rubber mallet to tap the rings on, and start the reassembly process. All said and done, a great product, great customer service, great delivery, great fit, and a great price!! Thx!