7 8" x 10 1 4" Simpson CHMXRD08710 SDS MAX Ground Rod Driver Blue Tapcon Screws The unique clip dimensions enable The unique clip dimensions enable easy installation on the open side of joists and rafters with up to 3 1 2" flanges and return lips up to 3 4" these screws provide strong clamping force and shear capacity in light gauge steel framing and panelized construction The Simpson Strong Tie® CHMXRD08710 ground rod driver is designed for driving grounding rods down through sand It is comprised of toughened steel and has gone through a specialized tempering process to create a hardened surface that is wear resistant