A coupling assembly, comprising: a first slide rail assembly comprising a first rail and a second rail , the first rail and the second rail being movable relative to each other; and a first cable management device , comprising: a first cable management arm ; a second cable management arm pivoted to the first cable management arm by a connecting base , the second cable management arm being pivotable relative to the first cable management arm ; an auxiliary member ; a first connecting member movably connected to the auxiliary member and configured to connect the auxiliary member with the first rail ; a second connecting member movably connected to the second cable management arm and configured to connect the second cable management arm with the second rail ; and at least one supporting member being movably configured on a bottom portion of the connecting base so as to support the first cable management arm and the second cable management arm ; wherein the auxiliary member is movable along a length direction of the first cable management arm , such that a length of the first cable management arm is increased when the auxiliary member is extracted. a first slide rail assembly comprising a first rail and a second rail , the first rail and the second rail being movable relative to each other; and a first cable management device , comprising: a first cable management arm ; a second cable management arm pivoted to the first cable management arm by a connecting base , the second cable management arm being pivotable relative to the first cable management arm ; an auxiliary member ; a first connecting member movably connected to the auxiliary member and configured to connect the auxiliary member with the first rail ; a second connecting member movably connected to the second cable management arm and configured to connect the second cable management arm with the second rail ; and at least one supporting member being movably configured on a bottom portion of the connecting base so as to support the first cable management arm and the second cable management arm ; wherein the auxiliary member is movable along a length direction of the first cable management arm , such that a length of the first cable management arm is increased when the auxiliary member is extracted. a first cable management arm ; a second cable management arm pivoted to the first cable management arm by a connecting base , the second cable management arm being pivotable relative to the first cable management arm ; an auxiliary member ; a first connecting member movably connected to the auxiliary member and configured to connect the auxiliary member with the first rail ; a second connecting member movably connected to the second cable management arm and configured to connect the second cable management arm with the second rail ; and at least one supporting member being movably configured on a bottom portion of the connecting base so as to support the first cable management arm and the second cable management arm ; wherein the auxiliary member is movable along a length direction of the first cable management arm , such that a length of the first cable management arm is increased when the auxiliary member is extracted. <EOS>