Industrial mounting frames are used with MMI's M-300 Series Lightning Arrestors for attaching units directly to ground rods (keeping lead inductance to a near-zero minimum). This mounting method provides the highest possible performance for
voltage protection. And they're built as if we're expecting you to be hit time after time. Upper horizontal mounting plate is pre-threaded and 1/2" thick solid 6061-T654 I aluminum bar stock. Set screw that holds assembly to ground rod is
stainless steel 1/4-20 Phillips head, balance of mounting hardware also 18-8 stainless steel. Boring of lower section is designed to comfortably fit top of ground rod by simply sliding the whole assembly over the top of the rod after
coating both surfaces with conductive copper-loaded anti-oxidant compound (provided). Bore, size is approximately .015-.020 larger than rod to keep the fit tight, the frame horizontal, and prevent entry of moisture, dirt, insects, etc.

Units are machined in one, two, and four-unit varieties indoor or outdoor use, accepts direct rain / snow exposure. Each unit is packed with anti-oxidant compound, #8-32 screws for arrestor chassis mounting, weight approximately 2 pounds.