Abstract: The unit comprises a tubular filler, provided with an internal thread) suitable for coupling with a corresponding external thread of the mouthpiece of the tank, and with, internally, a plurality of essentially coplanar anchoring prominences which, in the fitted condition, rest on part of the top edge of the mouthpiece of the tank to which they are constrained by fixing elements in such a way as to prevent the unscrewing of the filler. The anchoring prominences have respective retention elements protruding radially towards the centerline of the filler and capable of being opened out elastically towards the outside. The unit also comprises a filter with, at the top, an annular flange protruding radially towards the outside.

Abstract: The unit comprises a tubular filler, provided with an internal thread) suitable for coupling with a corresponding external thread of the mouthpiece of the tank, and with, internally, a plurality of essentially coplanar anchoring prominences which, in the fitted condition, rest on part of the top edge of the mouthpiece of the tank to which they are constrained by fixing elements in such a way as to prevent the unscrewing of the filler. The anchoring prominences have respective retention elements protruding radially towards the centreline of the filler and capable of being opened out elastically towards the outside. The unit also comprises a filter with, at the top, an annular flange protruding radially towards the outside.

Abstract: The device comprises a hollow external body, operationally arranged in a filler of the tank and anchored in which, with the interpositioning of a permanent magnet, is an internal body which defines an essentially tubular passage. The arrangement is such that when the nozzle of a urea solution distributor pistol is inserted into the passage of the internal body, the magnet causes an opening of an on/off valve in the pistol, permitting the input of a flow of the said solution into the tank. The device also comprises a filter through which the urea solution is intended to pass. At its end turned operatively towards the outside of the tank the internal body is provided with suitable means of connection for snapping onto corresponding retention formations provided in the external body, and the filter is integrated with the end of the external body intended to be turned towards the inside of the tank.