This article presents the MEG II Cylindrical Drift CHamber (CDCH), a key detector for the phase 2 of MEG, which aims at reaching a sensitivity level of the order of $6 times 10^{-14}$ for the charged Lepton Flavour Violating $mu^+ rightarrow mbox{e}^+ gamma$ decay. CDCH is designed to overcome the limitations of the MEG $mbox{e}^+$ tracker and guarantee the proper operation at high rates with long-term detector stability. CDCH is a low-mass unique volume detector with high granularity: 9 layers of 192 drift cells, few mm wide, defined by $approx 12000$ wires in a stereo configuration for longitudinal hit localization. The total radiation length is $1.5 times 10^{-3}$ $mbox{X}_0$, thus minimizing the Multiple Coulomb Scattering (MCS) contribution and allowing for a single-hit resolution of 110 $mu$m and a momentum resolution of 130 keV/c. CDCH integration into the MEG II experimental apparatus will start in this year.
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