2 7/8" X 4" (72mm X 101mm)

(ear side - inkstamp) 

{Rosenthal}

Picture courtesy Bob Berry

2 3/4" X 3 7/8" (69mm X 98mm)

(Ear incuse) J S

{Joseph Schachtel}

Picture courtesy Dominik Kałużny

2 3/4" X 3 7/8" (69mm X 98mm)

(skirt incuse) 

{AEG}

Picture courtesy Bob Berry

2 3/4" X 3 7/8" (69mm X 98mm)

No markings

Picture courtesy Dominik Kałużny

2 3/4" X 3 7/8" (69mm X 98mm)

(dome) 

{Kloster Veilsdorf}

Picture courtesy Bob Scafe

2 3/4" X 3 7/8" (69mm X 98mm)

(Ear top incuse) PHK

{Hermsdorf}

Picture courtesy Barrett Nicpon