The 14.01.202 key for the main spindle bar clamping collet sleeve is a precision component designed for the bar clamping group of Gildemeister-DMG Mori GM20AC, AS20 and GS20 multi-spindle lathes in the configuration for machining bars up to 20mm maximum diameter. Its main function is to provide the mechanical connection between the 9012E bar clamping collet and the 1401251 collet sleeve, preventing relative rotation between the two elements and allowing integral rotation to be transmitted inside the main spindle. Through the mounting seat machined in sleeve 1401251, the key works as a drive and locating element: it keeps the collet in the correct angular position, ensures continuity of rotary motion between sleeve and collet and allows the clamping system to follow the spindle rotation consistently during the machining cycle. In machine operation, sleeve 1401251 receives the axial action of draw tube 1501352 and converts pullback into radial closure of collet 9012E on the tapered coupling surfaces; key 1401202 completes this kinematic function by preventing the collet from rotating freely in its seat and by ensuring that bar clamping takes place with stable orientation, correct drive and no unwanted angular slipping. Although small in size, this component has an important technical role in the overall stability of the main spindle group, because an incorrect coupling may generate torsional play, localized wear, loss of phase between collet and sleeve, vibration, micro impacts and reduced clamping repeatability. The key is therefore part of the bar gripping kinematic chain: it connects the rotary motion of the main spindle to the bar clamping collet, supports the functional concentricity of the bar, contributes to stability during feeding and rotation and ensures that the clamping system works in coordination with the spindle drum, main spindles, possible front tool spindles, radial and axial slides and auxiliary systems of the machine. Its efficiency is especially important in automatic bar machining, where any discontinuity in rotary drive can affect dimensional accuracy, surface quality, repeatability of positions, cutting stability, form errors and control of workpiece geometry. From a maintenance point of view, key 1401202 is normally replaced when sleeve 1401251 is replaced, in order to prevent an already marked, deformed or worn element from compromising the correct fit with the new sleeve seat. Wear on the sides, rounded edges, compression marks, play in the seat or rubbing marks indicate reduced drive capability and may cause instability of the collet during rotation. In these cases, replacing the key restores correct torque transmission, maintains the angular position of collet 9012E and preserves the effectiveness of sleeve 1401251 in the clamping system. For preventive and extraordinary maintenance departments, automatic turning shops, machine tool builders, automotive production and precision engineering, the 14.01.202 key is an essential technical spare part for maintaining clamping reliability, production continuity and correct kinematic behavior of the main spindle. Tadaah offers this component as a functional part of the bar clamping collet sleeve group, to be evaluated not only as a fastening element but also as a rotational transmission and collet orientation control part within the bar clamping chain.