Abstract: A homokinetic universal joint drive line coupling device which comprises a drive shaft, a driven shaft and two yokes each of them being affixed to one of the shafts and pivotally engaging a respective gimbal ring at one of its diameters, both of the gimbal rings being arranged concentrically while the pivot points are aligned with each other along a diameter when the two shafts are in line. The device is also provided with two diametrically opposed pivot members which pivotally engage the two intervening concentric gimbal rings, an auxiliary universal joint, concentric to said gimbal rings and idly engaging the two converging shafts. The spider of the supporting universal joint are mounted pivotally at a concentric diameter perpendicular to the diameter of the yoke pivot points through one of the gimbal rings while the auxiliary joint yoke is at all times, when the shafts are aligned, with the spider pivot points located on the same diameter as the pivot members joining the two rings.