Female 29/32 Joint (Bistabil) on 36mm(OD) x 2.8mm(WALL) x 130mm(LENGTH) Tubing ?All Lenz joints are made of Schott Duran tubing by Herbert Arnold Robotics in Germany to extremely precise tolerances. Ground Joint Features Produced on DURAN tubing High taper accuracy of the cones Precise concentricity Small roughness of the surface Excellent tightness No bend out of line Lenz ground joints are produced according to the standard DIN 12242 / ISO 393. Each production step is tested by a quality management system, based on DIN ISO 9001 / EN 29001. The tests are examined by a cone measuring device for checking the taper, a surface roughness meter for testing the roughness parameters and a wall thickness measuring apparatus with a magnetic inductive measuring process to guarantee a homogenous concentricity and wall thickness.