3 3/4" X 3 3/4" (92mm X 92mm)

No markings

Picture courtesy Bill Ostrander

3 3/4" X 3 5/8" (92mm X 90mm)

(ear incuse) 1-22

Picture courtesy Bob Berry

3 3/4" X 3 3/4" (92mm X 92mm)

(upper skirt) NZI / MADE IN / NEW ZEALAND / 1950

{New Zealand Insulators}

Picture courtesy Bob Scafe