Material: The shell of our box cutter knife is made of ABS, silicone and alloy steel, with non-slip stripes, thickened scabbard, comfortable to hold, and not easy to rust. SK-5 high carbon steel blade is sharp and durable, it can easily complete the cutting work. Quick Change Blades Mechanism: There is a metal piece in front of the black slider. Press the metal piece to take out the old blade. Press the black switch of the tail, pull it back at the same time to take out the blade storage box, then install a new blade into it. Automatic Locking: There are serrations on one side of the scabbard, which can stuck the slider and automatically lock the box cutter blades. Push the black slider to extend and retract the blade, easy to use. Blade Storage Design: There is a blades storage box in the box knife, which can store up to three blades. These utility knife blades is snap off blades. You can break off the blade head to renew it.