Caterpillar 440c Original Filipino Balisong butterfly Knife BF-20

The BF-20 Caterpillar is one of only two knives in this series built at the traditional 29cm size rather than 24cm. Brass frame, bone inserts, 440C blade, 14cm of it, 220g on the scale. If you have been flipping a 24cm knife and it has started to feel small, this is the size the craft was actually built around and this page is about what changes when you go up.

Veinte y nueve: 29cm is the original standard

The old Batangas measurement was veinte y nueve, twenty-nine, meaning 29cm open. That was the full-size balisong before smaller frames became the norm for pocket carry and for flipping in a flat. The BF-20 is built to that measurement.

This is not a novelty size. It is the size, and the 24cm knives are the compromise. We sell plenty of the compromise and we like it, but the history runs the other way round from how most shops present it.

What 5cm and 45 grams do to the flip

The honest summary: a 29cm knife is more impressive and less convenient. Rotations are slower, which some people find easier to read and time, and which others find sluggish. Aerials need genuine ceiling height. If you flip sitting down in a small room you will hit something.

Who should size up

• Anyone with large hands who has been quietly finding 24cm handles cramped.
• Flippers who want their tricks to be readable on camera. Longer knife, bigger arc, clearer to watch.
• People who care about the traditional pattern and want the size that goes with it.
• Anyone using the knife as a knife rather than only as a flipper. 14cm of blade is a real cutting length.

Who should not: anyone learning their first rollovers, and anyone who mostly flips in a chair.

Specifications for this 440C dagger balisong

The name

Long, segmented, and it moves in a wave rather than all at once. Watch a 29cm balisong roll over slowly next to a 24cm one and the name explains itself. Caterpillars are also not in a hurry, which is the correct way to flip this knife.

Bone panels on a long frame

The extra handle length means bigger bone inserts, which means more of the pore structure and density banding is visible on each panel. On a 24cm knife you get a section of bone. On this one you get a length of it, and the variation across the panel is much easier to see.

They will not match each other. Bone never does. Keep it out of long soaks and give it a drop of mineral oil once a year.

Steel: what 440C gives you on a 29cm butterfly knife

440C at about 58 HRC, the same as the rest of the series. Easy to bring back on a stone, tough when dropped, stainless enough to survive a humid pocket. On a 14cm blade the easy-sharpening part matters more than usual, because there is simply more edge to maintain.

Trainer version

Available unsharpened at the same price from the option above Add to Cart. On a 220g knife at this length we would push the trainer harder than usual: a big knife rotating slowly gives you more time to make a mistake in, and 220g arriving on a knuckle is memorable.

Shipping a 29cm balisong

Free across the United States, flat $49 worldwide however large the order. Fitted leather sheath cut for the 29cm frame, included.

the 440C is hardened to 58-60 HRC, which is the window where it holds an edge without turning brittle on you.