Brownells Oxpho-Blue Cold Bluing Features Oxpho-Blue is formulated to simplify the bluing process while delivering strong lasting results. The gun bluing solution penetrates oil and surface contaminants allowing it to clean remove light rust and blue the steel simultaneously. Its unique chemistry forms a phosphate-like layer beneath the finish enhancing durability and resistance to wear and weather. Ease of application makes it accessible for a wide range of users from hobbyists to experienced gunsmiths. The liquid can be applied with a cloth using simple rubbing techniques producing a uniform and attractive finish with minimal effort. Unlike many traditional solutions it resists after-rust and continues to improve in appearance with additional application and polishing. Brownells Oxpho-Blue Cold Bluing Specifications Manufacturer: Brownells Model: Oxpho-Blue Cold Bluing Type: Cold Bluing Solution Application: Steel Firearm Surfaces Tools Container Size: 4 fl oz Volume: 118 ml Finish Type: Chemical Bluing Properties: Rust Removal Corrosion Resistance Oil Penetration