Review on 🔪 X-Acto Retractable Blade Knife Refill Blades - 5/Pkg: Reliable Replacement Blades for Precision Cutting by Sasha Hsiao

Like other reviewers, I had trouble fitting the blades to the old pocket knife #209 (https://www.amazon.com/Retractable-Precision-Utility). -Knife-Blade/dp/B072XVWQFW/ref=sr_1_5?keywords=X-acto+Retractable+Blade&qid=1565731667&s=gateway&sr=8-5) However, these are the only replacement parts I could find online for it, so I have it anyway bought them to see if i can insert them. Replacement knives fit the old model, but with some effort. The problem isn't mounting them, it's that they don't retract (stick) smoothly. You will need to cut off the plastic underside of each replacement blade with scissors. Remove just enough and it will fit snugly and not snag on the side of the handlebars. Once you install them they work as expected, nice and sharp!