Abstract: A filler cap for a liquid receptacle within a vehicle. The filler cap includes a first body part (1) having an essentially cylindrical construction with a first end (1a) and second end (1b). The first end (1a) of the first body part (1) includes a means for concentrically engaging a receptacle opening neck 5. The second end (1b) of the first body part (1) has a second body part (2) pivotally attached thereto along a pivot axis (3). The pivot axis (3) intersects a longitudinal center axis (4) of the first body part (1) at an essentially right angle. The second body part (2) is moveable between a rest position and an operating position. In the rest position, the second body part (2) is essentially aligned with a plane of the second end of the first body part (1). In the operating position, the second body part (2) is essentially orthogonal to the plane of the second end of the first body part (1).