PROFORM Black Racing Series Carburetors with Black Diamond coating used on the main body and fuel bowls provides a durable finish which is impact resistant, and reduces fuel temperature based on thermal testing for enhanced performance. It is impervious to virtually all under hood chemicals and fuels, and is corrosion resistant. Each carburetor is hand assembled and tested in the U.S. utilizing the PROFORM High-Flow Carburetor Main Body, durable billet metering blocks, high performance billet throttle baseplate, and lightweight aluminum fuel bowls. PROFORM Black Race Series Carbs include Adjustable High-Flow Aluminum Main Body with Screw-In Air Bleeds, No Air Horn, Choke Tower, or Choke Control. Billet Throttle Base Plates have Adjustable Secondary Air Flow Cam Bracket, Solid Billet Construction, Timed and Full Vacuum Tubes for Tuning and Accessories, Button Torx Head Throttle Plate Screws, Power Valve Blow Out Protection, Progressive Slip Link Mechanical Secondary Linkage, Serviceable Throttle Levers, and Ford Kickdown. Billet Metering Blocks feature Solid Billet Construction, Durable, No Warping or Porosity Problems, and Changeable Idle Feed Restriction and are Manufactured in the U.S.A.! Aluminum Fuel Bowls feature Lightweight Aluminum Sight Glass Windows for easy float adjustment! Sold Individually.