guide bushing 1,Materials: HSS M2, SKH9, SKD11 2,Tolerance: less ... 3,Working life: 20,0000times 4,8-10 work days guide bushing Type circular, Square Header , hexagonal , R-shaped…MaterialHSS ... , China(Mainland)Machine TypePunching Machine Please specify the details of guide bushing as follows when you inquiry1,The shape of punches ... the best to provide your own drawings.6,We can design as your inquiry