I was surprised to discover this recently. A butterfly deba. Apparently Daiwa makes several butterfly style fishing knives. : r/knives

The Barber Balisong Butterfly Knife Straight Razor

What's Next? : r/knifeclub

butterfly fish are impossible for me i dont know why?

Butterfly Knife, Trainer Practice Tool Steel Metal Folding Knife Unsharpened Butterfly Knife Comb for Practicing Flipping Tricks (Black and Silver, Set of 2) : : Sports & Outdoors

Help Identifying butterfly knife. : r/knifeclub

2PCS Butterfly Knife, Stainless Steel Practice Training Tool, Butterfly Trainer for Beginners Practicing Flipping Tricks, 100% Safe and Durable, Metal Folding Knife Unsharpened Butterfly Knife (Set of 2, Black and Silver, ) : : Sports & Outdoors

MoyeWorks Balisong 902 Pretty Guys Butterfly Knife TC21 Titanium Comb Practice Training Bladeless Foldable Survival Beginner

Noob question on fillet knives : r/sharpening

Fillet knife vs deba Kitchen Knife Forums

Dragon Totem Stainless Steel Comb Dragon Totem Stainless Steel Practice Butterfly Knife Trainer and Comb Knife Trainer : : Sports & Outdoors