The leaf Spring Mounting Brackets (pair) allows the Twirler to be attached to the rear leaf spring bracket on your car. These may be used on a wide variety of vehicles equipped with a leaf spring mounting system and no rear valence attachment points. Applicable to post ’71 Mustangs, A & E body Mopars, Nova and many others. Customer must set height and depth of mount and weld into location. Most full-framed vehicles will require no addl brackets other than the mounting that comes with the Auto Twirler (brackets are normally for unibod apps). Unpainted. Includes instructions. 1 yr mfr. warranty. Made in USA.