You bought a new ST300, there was an issue. You returned to LM as a warranty claim, correct?
This process has been repeated multiple times?
And, most current unit, the tools lock, but the lock released tabs do not appear to be locked?
Check the date code on each handle, if new I would suspect the date codes should be within 6 months or later.
Could be LM is just recycling No problem found tools from one user to another. Unless you requested your tool to be repaired and returned I could see this occurring.
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