Fit System 80900 Chevrolet/GMC/Cadillac Towing Mirror - Pair Easy to install, no hardware required or holes to drill, as the custom fit allows mirror to snap on over existing mirror Engineered to conform to original equipment look, fit, and finish without the hefty price tag Very versatile; a snap to install, can remain on and fold away with the existing mirror, or can easily be removed and stored for later use Significantly expands your field of vision to comfortably see more when towing Custom design allows for secure and snug fit with no slipping off NOTE: There is an adjustment screw on the bottom of mirror extension. There is a small hole on the bottom of the mirror. Tighten the screw holding the mirror extension in place and it will greatly reduce the vibration OEM Look OEM Fit and Finish Easily Removeable in Needed