Adapter Plate (M-706188) Mercury Quick Change Trim Anode - Long Life. Aluminum adapter plate with a single stainless steel 10/32 threaded insert for attaching the anode. The specially designed ridge holds the anode securly and tests prove longer life for the anodes installed. M-706188 Adapter is used in conjuction with M-706189 and M-706190 quick change anodes. For both zinc and alluminum anodes. Come with attaching screws, that go directly into the original anode placement holes.