单项选择题
A.15N/cm B.20N/cm C.25N/cm D.30N/cm
A.男鞋用勾心,适用跟高20mm B.女鞋和儿童用用勾心,适用跟高20mm C.女鞋用勾心,适用跟高20mm D.儿童用勾心,适用跟高20mm
A.I型勾心、L型勾心、Y型勾心 B.I型勾心、L型勾心、Y型勾心、T型勾心 C.I型勾心、L型勾心 D.I型勾心、Y型勾心