This is a Replacement Stainless Steel Piston which fits Kodiak 225 Sized Calipers. This piston measures 2 1/4" for maximum stopping strength. Typically when installing this the Piston Seal and Piston Dust Boot are also replaced, as you will have these components taken out already, replacement is easy.
The Manufacturer's Part # is: DBC-225-PISTON-SS