Device for attaching a nozzle holder to a fluid supply line of a spray system, said device being configured to attach a nozzle holder comprising a body (10a, 10b, 10c) and a casing to a supply line, the supply line extending between the body (10a, 10b, 10c) of the nozzle holder and the casing of the nozzle holder, the attachment device comprising: - at least one receiving support configured for cylindrical surface contact with the supply line; - at least one latch; - a receiving support hinge allowing the latch to pivot about a first pivot axis (700, 800) parallel to the direction of the supply line, the latch being movable between a closed position in which the latch surrounds the supply line on an outer periphery of the supply line and an open position in which the contact between the receiving support and the supply line can be broken; the device being characterized in that the device further comprises - a receiving support pin for locking the latch in the closed position by insertion into coaxial holes of the latch and of the receiving support, the pin comprising a clamping collar which is elastically deformable into an undeformed initial shape, said pin being pivotable about a second pivot axis (700, 800) parallel to the first pivot axis (700, 800) between a clamping position in which the clamping collar is elastically deformed to surround and clamp the outer periphery of the supply line by a snap fit, and a free position in which the clamping collar is left free in its initial shape, the contact between the clamping collar and the supply line being broken; - the clamping collar of the pin comprising an eccentric protruding radially relative to the direction of the supply line, the eccentric being configured, in the clamping position of the pin, to cover the latch. - at least one receiving support configured for cylindrical surface contact with the supply line; - at least one latch; - a receiving support hinge allowing the latch to pivot about a first pivot axis (700, 800) parallel to the direction of the supply line, the latch being movable between a closed position in which the latch surrounds the supply line on an outer periphery of the supply line and an open position in which the contact between the receiving support and the supply line can be broken; the device being characterized in that the device further comprises - a receiving support pin for locking the latch in the closed position by insertion into coaxial holes of the latch and of the receiving support, the pin comprising a clamping collar which is elastically deformable into an undeformed initial shape, said pin being pivotable about a second pivot axis (700, 800) parallel to the first pivot axis (700, 800) between a clamping position in which the clamping collar is elastically deformed to surround and clamp the outer periphery of the supply line by a snap fit, and a free position in which the clamping collar is left free in its initial shape, the contact between the clamping collar and the supply line being broken; - the clamping collar of the pin comprising an eccentric protruding radially relative to the direction of the supply line, the eccentric being configured, in the clamping position of the pin, to cover the latch.