Press the thumb button and fully retract the blade into the knife's housing.
Use the flat-head screwdriver, if needed, to open the knife's housing. On older models there is one screw holding the housing together. On newer models the housing opens by releasing a tab or rotating a portion of the knife open.
Remove the dulled razor blade with caution to prevent cutting yourself. Insert the new blade.
Close the knife housing. Press the thumb button to test whether the blade will expose and retract properly. Dispose of the used blade safely.
Things You Will Need
- Flat head screwdriver
- In most models, you can use both ends of the razor blade in the knife, so changing the blade may just mean flipping over the razor blade. To avoid confusion over whether or not an end has been used, mark used ends with a permanent marker.