This product is a set of four developer units compatible with select - including 2555C, 3055C, 3555C, 4555C, 5055C, 2000AC, 2500AC, 2050C, 2550C, and 2051C.Model number: T-FC50.Designed for use in FC505 developer units.Available in black, cyan, magenta, and yellow.Powder form with consistent tint and no agglomeration.Page yield based on 5% coverage.Defective rate less than 0.5%.Packaging options include bulk, bag, and bottle.Tested for mechanical stability, environmental resistance over one year, and print quality including color accuracy, absence of stains, and resistance to fading.