The material of Seam ripper is bearing steel, It have excellent hardness , resistance , sharp edge and good durability. 100pcs/box, 2000pcs/ctnThe material of Seam ripper is bearing steel, It have excellent hardness , resistance , sharp edge and good durability. The edge is sharpen by grinding machine, Thus, the shape and sharpness are perfect. The knife body is fixed well on plastic handle. Its ...