13 pcs Pen Cutter Precision Knives x-acto knife1set = 13 PCS Material: high carbon steel Size: shank diameter: 8 18 10 (mm) full length: 105 (mm) Multi function, multi head, paper cutting knife, the tip can be easily disassembled, sharp knife, and durable. [For] the majority of paper cut enthusiasts, beginner paper cut, hand beginner, student paper cut, hand school lesson, cheap affordable, the price equivalent to the price of the blade, you can buy a few to spare.