Specification 1) thick: A-clase material has 0.1mm, 0.15mm 0.20mm, 0.25mm four kinds; B-clase material has 0.1mm, 0.12mm, 0.15mm, 0.20mm, 0.25mm five kinds. 2) length: 7mm~ 15mm 3) package: common case or high-grade case. 4) quantity: 90pieces per case. 5) curl: J; C two kinds.