Edelbrock heat exchanger part #15409 is a dual pass/single row design and delivers 26,700 btu/hr Includes a 3/4in. barbed inlet and outlet for plumbing, along with M6x1.0 threaded bungs for mounting. Heat exchanger part #is a Dual Pass/Single Row Universal Heat Exchanger with the following dimensions (17in. W x 11in. H x 2in. D) with 4 threaded bungs. Edelbrock offers a wide selection of Universal Heat Exchangers to work with the Edelbrock Universal or Enforcer Supercharger systems. Edelbrock heat exchangers offer reliability and durable construction for high Performance's street applications.