Torque Solution Billet Dual Pass Flex Sensor BracketTorque Solution Billet Dual Pass Flex Fuel Sensor Bracket for GM Flex Fuel Sensors part #(s) 13577429, 13507128, 13507129. Will also fit Cobb Flex Fuel Sensors. Our flex fuel sensor billet dual pass bracket is the perfect solution when making a custom fuel setup and you would like to place or relocate the flex fuel sensor to the area of your liking. Features a high flow dual pass 10 design for maximum fuel flow to be able to be placed on either the