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

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

2pcs Butterfly Knife Trainning Practice Comb Unsharpened Blade for Practicing

Dragon Totem Stainless Steel Comb Dragon Totem Stainless Steel Practice Butterfly Knife Trainer and Comb Knife Trainer

Fillet knife vs deba Kitchen Knife Forums

Noob question on fillet knives : r/sharpening

The Barber Balisong Butterfly Knife Straight Razor

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

Reviews and Ratings for Sergey Rogovets Custom B2 Balisong Butterfly Knife 5.125 S45VN Double Edge Kris Blade, Titanium Handles with White Storm FatCarbon Inlays - KnifeCenter - Kris B2

Help Identifying butterfly knife. : r/knifeclub