Key Hole Mount Explained

What is an HDU Key Hole Mount?

A key hole mount allows for the simple installation of an HDU Sign to wood post without compromising the sign's face. The key hole mount is installed to the back side of an HDU Sign during fabrication. A cavity is carved out to accommodate a 1/4" polycarbonate plate.  The 1/4" polycarbonate plate with pre-spaced keyhole slots is precision-carved to fit snugly into the cavity, and then secured in place with epoxy resin. The key hole plate becomes permanently integrated into the back of the HDU Sign, ensuring for a sturdy and durable installation.

Installation of the HDU sign is relatively simple. Installer pre-drills holes in post at specified location, inserts bolts, hangs sign on head of bolt and then securely tightens nut.


  • - An overall HDU thickness of at least 1.5".
  • - Galvanized or stainless steel bolt sets.
  • - Beginner to intermediate skill level of the installer.