I have several Stanley knives. This one is by far the worst design of the lot. You must slide the blade fully out before attempting to open the knife for blade replacement. Instead of using a screwdriver to open it and find the on-board blades, you push a button that looks like a screw. This makes it less safe. The slide is more stiff than their other blades and putting it back together in the open position is more difficult, also. The visual instructions leave something to be desired, but you can figure it out. I should have known better than to buy online. I should have tested them out in person. This is the least comfortable blade I've purchased from Stanley.