MARKINGS: Code marking will be found inside handle. Markings must be clear. Prior to 1972, Klein used a three letter date code system based on these letters: M K L E I N C O R P
The first letter = quarter of manufacture
Last two letters = year of manufacture (19 __).
Examples:
LIN= 3rd Quarter, 1956
KNR = 2nd Quarter, 1969
Earlier turn of the century pliers may simply use a date code of a month and a year. Example: 1-12 = January, 1912
The offer begins March 1, 2013 and ends May 31, 2013. You may send entry forms for as many different Klein Side-Cutting Pliers as you choose, but only one entry per pair of pliers will be judged. This offer is not open to past or present employees of Klein Tools, Inc. or advertising and sales agents serving Klein Tools, Inc. A decision regarding which pliers are the oldest will be made by Klein Tools’ engineering team consisting of 5 members in their sole judgment. In case of a tie, the payments will be divided among the successful entrants. Offer valid for US residents only.
The oldest pliers, once identified, will be purchased by Klein Tools® for the sum of $2500 in cash and $2500 (based on minimum advertised price) in new Klein® tools. The qualifying entrant may decide which Klein® tools will be given.
Look for a Central Hinge or Standard Leverage Pliers.
Klein Tools introduced Hi-Leverage Pliers in 1951. While we still make standard leverage pliers today the central hinge can sometimes be an indicator of the pliers' age.
Block or square type pliers head. Over the years electricians requested a smoother more machined New England Style head for bending and twisting wire. Older Klein plier heads may be more squared off resembling the picture on the right.