This $8 Knife Is the One Purchase You Must Make Before Prime Day

Like many Americans, I bemoan the fact that online shopping hurts local businesses, which can't compete with the convenience of unsustainable perks like "free" two-day Prime shipping. Like many Americans, I still buy a ton of stuff online anyway, because it's sure easier not to have to carry a huge pack of toilet paper home from Aldi (at least, as a New Yorker, I can still be a snob about the fact that I walk to buy groceries). But this also means that, come Prime Day or during the holiday season, I have to deal with a whole lot of cardboard boxes.

Some 35 million tons of "containerboard," or cardboard used to make shipping containers like Amazon boxes, is produced in the U.S. each year. By my estimate, at least 10 percent of that arrives on my doorstep. And while I'm super diligent about recycling all of it (the American Forest & Paper Association estimates that the "effective recycling rate" for cardboard is as high as 85%-yay!), breaking those boxes down to get them ready to place curbside can be a hassle. Or it was, until I learned about the Canary box cutter, a slim little knife with a non-stick serrated blade and a cheery yellow handle.

CANARY Corrugated Cardboard Cutter, Made in Japan, Yellow $8.20 at Amazon $12.00 Save $3.80 Shop Now Shop Now $8.20 at Amazon $12.00 Save $3.80 A box cutter produced by a former Japanese sword company

This $8 knife-yes, it is sold on Amazon, though mine was shipped to me in a padded envelope rather than a box-is made in Japan by a company called Hasegawa Cutlery, which got its start nearly 100 years ago polishing and grinding swords (the "Cutlery" part was added to the name after World War II, when the business first began producing scissors). Hasegawa's marketing language suggests that the company brought all of its Japanese sword-making expertise to bear on creating consumer goods, and while I've never tried to break down a stack of shipping boxes with a sword, I can't imagine it'd be much easier than using my Canary.

My previous methods for cutting through cardboard-kitchen scissors or a steak knife (don't be like me, kids!)-were less than effective, and utility knives, though certainly an improvement, aren't great at the task either. Cardboard is stiff and fibrous, so while a razor blade can slice through it pretty easily, it's hard to use one to make a controlled cut, as the blade will careen off-course if you try to go against the "grain," so to speak; utility blades also dull quickly but will still remain sharp enough to easily cut you if you handle them incorrectly.

The all-around serrated edges of the Canary, on the other hand, seem to cut through cardboard like butter, whether you're going with or against the grain, pushing the blade or pulling it, or making a sawing motion; it lasts much longer, and won't cut you nearly as easily. This has made the Canary a favorite of crafters who work with cardboard.

I'm not the crafting type, but I've used my Canary on boxes both small and large. In about a minute, I cut down the big box my dehumidifier shipped in, leaving a neat stack of small pieces of cardboard that are easy to tie up for recycling. The knife works equally well on the lighter cardboard boxes like those Amazon uses, and thicker ones, like the beefy boys that held my Target flatpack furniture.

It seems a stretch to call this little blade life-changing, but it has definitely saved me a lot of time-much more than $8 worth.