Cleco 10010115 RBI 256 Microstop Cage, Tapped Mounting Base w/ Nylon Nose Product Image May Not Reflect Actual Model. The Cleco 10010115 RBI 256 Microstop Cage, Tapped Mounting Base w/ Nylon Nose features a cemented, hardened and ground chrome-nickel steel spindle mounted on a self lubrificating bronze body and a thrust bearing. Centring-cone of the cutter (120°) for perfect concentricity. Microstop depth adjustment (1 scale division = .001”). Microstop depth setting is held securely in place by locknut with seal. This patented feature allows an easy loosening of the locknut without damage to the drill cage. Different mounting bases available. For special composites mounting base with vacuum.