The SG-8 is a square, steel grille with a square perforation pattern and beveled edges. Precision formed from single piece of 22-gauge steel, it features an open chipboard gasket and four 8-32 x 3/4" welded studs with hex nuts for concealed mounting of an 8" EIA speaker or Lowell’s narrow-profile Unihorn (Model LUH- 15T) with 3.72"D. It’s equipped with white 8-32 Philips-head screws to attach the speaker/grille assembly to a recessed or surface backbox.