Dating Plomb Era Tools

Date Codes - Date codes were used on Plomb tools (most, not all) from 1927 to 1945.

1927 - "7" followed by a letter. The "O" in Plomb was a normal O, and the tools were stamped Los Angeles.

1928 - "8" followed by a letter. The "O" in Plomb was a normal O, and the tools were stamped Los Angeles.

1929 - "9" followed by a letter. The "O" in Plomb was a normal O, and the tools were stamped Los Angeles.

1930 - "0" followed by a letter. The "O" in Plomb was a normal O, and the tools were stamped Los Angeles.

1931 - "1" followed by a letter. The "O" in Plomb was a normal O, and the tools were stamped Los Angeles.

1932 - "2" followed by a letter. The "O" in Plomb was a normal O, and the tools were stamped Los Angeles.

1933 - "3" followed by a letter. The "O" in Plomb was a normal O, and the tools were stamped Los Angeles.

1934 - "4" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped Los Angeles.

1935 - "5" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped Los Angeles.

1936 - "6" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped Los Angeles.

1937 - "7" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped Los Angeles.

1938 - "8" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped Los Angeles.

Early 1939 - "9" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools in Early 1939 were stamped Los Angeles.

Late 1939 - "9" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools in Late 1939 were stamped "Made in U.S.A."

1940 - "0" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1941 - "1" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1941 December - 2 letter coding system begins for War Production, second letter would be A, first letter represents the month (only L representing December) (We have not seen an example of a tool stamped representing this identification method and are doubtful a "LA" coded tool exists including the aforementioned markings.)

1942 January = November - "2" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1942 - 2 letter coding system for War Production, second letter would be B, first letter represents the month (A through L = January through December respectively).  The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1943 - 2 letter coding system for War Production, second letter would be C, first letter represents the month (A through L = January through December respectively).  The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1944 - 2 letter coding system for War Production, second letter would be D, first letter represents the month (A through L = January through December respectively).  The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1945 - 2 letter coding system for War Production, second letter would be E, first letter represents the month (A through L = January through December respectively).  The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1945 - "5" followed by a letter. The "O" in Plomb was represented by an upside down triangle, and the tools were stamped "Made in U.S.A."

1946 - Early 1947 - Tools marked with NO DATE CODE, and stamped "Made in U.S.A."

Early 1947 - January 1, 1949 - Tools marked with no date code, and stamped "MFD. U.S.A."

January 1, 1949 - March 24, 1950 - Tools marked "Proto by Plomb Tool Company."  All "O" alphas are represented by the upside-down triangle.  Tools marked with no date code, and stamped "MFD USA" (Notice the absence of dots in U.S.A.)  The wrench sizes are stamped in a small rectangular "pebble field," and all information is stamped on the same side of the shank, where the box offset is facing up.

Proto LA Era - 1950 to 1956

Combination Wrenches

For combination wrenches, at least 2 distinct styles were used during this period.  Style 1: the pebble field and information are all stamped on the same side of the shank, where the box offset is facing up, as in this example.  We believe this style to represent only the first 1 or 2 years of production.  Reasoning: 1. This is the same manner in which the immediately prior transition style combination wrenches were stamped.  2. This style appears to be comparatively scarcer than the next style.

Style 2: stamped with only the Pebble field sizes on the shank, where the box offset is facing up, and the model number, PROTO Los Angeles, MFD USA is stamped on the opposing shank, as in this example.  We submit that this style was produced for the majority of the Proto LA time period as they appear to be much more prevalant amongst our inventory.

DOE / DBE Style Wrenches

All DBE wrenches were stamped with both the pebble field and brand/model stamp on the same side of the shank, where the larger size box offset is pointing up and on the viewer's left, as in this example.

All DOE wrenches were stamped with both the pebble field and brand/model stamp on the same side of the shank, where the larger opening is on the viewers left, and offset pointed toward the viewer, as in this example.

Other Tools

We have found only one style of stamping for Proto LA era sockets.  Some breaker bars and ratchets retained their full pebble field from the Plomb and Transition era for at least the beginning of this timeframe.  Specialty wrenches, such as tappets and other wrenches appear to have never received a "pebble field" stamp and retained all size, model, etc. information on one side of the shank, leaving the other side blank.