This is a brand new K in extreme flow air filter. Best you can buy. I used them for years. I sold my kx I never got to use the back up filter so no need and leaving it sitting in the shop forever. A for sale it goes fixed 2006 two well I forget now the model number is KA – 4519 extreme duty I’ll have to look and find out what all models this fits. I know it fits a 2015 because that’s what I had. I’ll find out an update.