As anyone who has cut aluminum ducts will know, the product itself has a spiral shape, and to cut it vertically, I made a cut with a cutter and cut it carefully with scissors. Even with this method, it's hard to think about it, but with Kirimawashi, I was able to cut it cleanly in one shot. It cuts with push-cutting, but it can be easily cut with a little knack. This product is recommended.
(Translated by machine.)