Knife that opens like nutcracker marked Rostfrei 420 What do I call this ?

[doxietreasures]

When folded 5 1/4". When opened 9 1/2". Blade 4"  Heavy design. Do you know the age and what type of knife is it ?

[solidguitar1961]

Butterfly knife

[lacemaker3]

@doxietreasures 

FYI -- butterfly knives can't be listed or sold on eBay USA. They're prohibited.

https://www.ebay.com/help/policies/prohibited-restricted-items/knives-policy?id=5047

[worldcoinauctions]

Balisong knife, also known by an unlistable name. Cool one, probably early 80s.

[kh-taylarie]

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