The four PINS started 1974 or just after.

The four DOTS started in 1981.

There are a few exceptions and sometimes a few months slopover in production, but those are the generally accepted dates.

There was even a five-pin model after 1974 for a while.

Pins refers to the rivets that hold the wood inlays on plus the rocker rivet.

Dots refers to the stamped dots on the blade.

Last edited by DancesWithGuns; 05/22/15.

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