Lettering "1", "2", or "3" has been observed on the bottom of the bases on the left or right side. Max Schlenker said these are "cavity numbers" to identify the cavity used to cast the base.
Base Cavity Number "1" Left:
The numeral "1" on the bottom of the base at the left.
Base Cavity Number "1" Right:
The numeral "1" on the bottom of the base at the right.
Base Cavity Number "2" Left:
The numeral "2" on the bottom of the base at the left.
Base Cavity Number "2" Right:
The numeral "2" on the bottom of the base at the right.
Base Cavity Number "3" Left:
The numeral "3" on the bottom of the base at the left.
