(Note: Measurements are outside max. dimensions unless stated otherwise).
18th Century : Flat plate escutcheon with chamfered edges.
OUTSIDE
Height 50mm. (1 15/16")
Width 49mm. (1 15/16")
Thickness (variable) 1mm. (1/16")
KEYHOLE
Height 17.5mm. (11/16")
Diam. of hole 7mm. (1/4")
Width at narrowest part of neck 5mm. (3/16")
Width at base of taper 6mm. (1/4")
Original would have had steep chamfered edges. Castings may require sharpening up with a needle file.