Strange French Opening Mechanism

[autoknife]

I picked this up a few months ago and wondered if any of you had seen this model before? I know of about 4 others in collections of friends of mine, but none of them are in mint condition, and none are etched like this one. To open (and close) the lever on the backspring must be lifted. Thanks....Ken

 

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Though I have never seen this particular French switchblade before, I know that several German manufacturers made switchbaldes with a backspring release (along to their range of LL release ones). Such German picklock knives were even made post WWII.
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