Paper cutter parts, Hidden blade design only work when you press the blade. Protect user's finger especially children. Keep your portable craft paper trimmer working at its best by replacing dull blades with new ones. It is not recommended to use this blade directly for paper cutting. It should be used with a sliding paper cutter. A titanium blade coating that is three times harder than steel improves durability for lasting value. Blade change method: Slide blade carriage to the center of the clear bar. The blade can be removed and replaced by pulling the two clear bars apart gently. Ecraft professional paper cutter blades can cut through vinyl, photo, picture, cardstock, coupon, scrapbook materials, and much more paper project