Seperate the unit CAREFULLY into its components. These are:
Front Guard Ring
One person will now take the rear diaphragm ring and hold it over the rear of the hole and another will take the front ring to the front of the hole and, inserting the screws, screw them through into the holes in the diaphragm ring until the unit is clamped securely to the glass.
Now screw in the locknuts.
Units Using Studs Screw dome nuts firmly onto studs. Now treat as long screws, screwing them into the threaded back ring. Now put on locknuts.
Installation into Double Glazing/Walls using a Cylinder (Requires 2 Melaphone Units)