Early bases are not as deep as later bases. Several variations in lettering exist.
Big 4 Base 2 "1-A"
Big 4 Base 2 "1-A"
Big 4 Base 2 "2-A"
Big 4 Base 2 "2-A"
Base 2:
Base is standard depth of 1 27/32 inches. The cavity number "1-A" or "2-A" has narrow spacing. The "69" at the bottom is center aligned with the "1-A" or "2-A". Used from ca. August 1934 through early 1938.
1-A [2-A] 69
Big 4 Base 3 "1-A"
Big 4 Base 3 "1-A"
Big 4 Base 3 "2-A"
Big 4 Base 3 "2-A"
Big 4 Base 3 "1-A"
Big 4 Base 3 "1-A"
Base 3:
Base is standard depth of 1 27/32 inches. The cavity number "1-A" or "2-A" has narrow spacing. The "69" at the bottom is right-aligned with the "1-A" or left-aligned with the "2-A". Used from ca.
April 1935 through the end of Style 4.
1-A [2-A] 69
Big 4 Base 4 "1-A"
Big 4 Base 4 "1-A"
Big 4 Base 4 "2-A"
Big 4 Base 4 "2-A"
Base 4:
Same as type 3 but has a hole in the center of the base. Base is standard depth of 1 27/32 inches. The cavity number "1-A" or "2-A" has narrow spacing. The "69" at the bottom is right-aligned with the "1-A" or left-aligned with the "2-A". Used from ca. mid-1936 through the end of Style 4.