Throttle Return Spring Bracket For 4150 & Edelbrock Carbs. Billet aluminum bracket can be used with cable or mechanical linkage. Bracket fastens to carb mounting studs and includes dual stainless steel return springs which are adjustable for tension. A specially designed return spring arm attaches to the carb for simplified installation and smooth operation. Low profile design clears most air cleaner assemblies. Note: Longer carburetor studs will be required to accommodate bracket.