Flexible Chuck 1.Screw dynamic balance design,for under RPM10.000. 2.The collet is optional of flexible,waterproof, rigid tap, flex tap, mini innerhole. 3.Offset precision of flex collet has A (less than 0.02mm),AA(less than 0.01mm).AAA(less than 0.005mm). 4.The collet must posted into screw ,then put it into the cutter ,and set it together with body. 5. Put the cutter into the collet,it must be over the availability hold length to avoid damage of locked.