Assembly for non-detachable connection of plastic parts for a car

An assembly for non-detachable connection of plastic parts for a car, the assembly comprising:

• a plastic first part,
• a plastic second part, and
• at least two pairs of complementary fastening elements, wherein a first element from each pair of complementary fastening elements is rigidly connected to the first part, and a second element from each pair of complementary fastening elements is rigidly connected to the second part, and
• wherein the first element from each pair of complementary fastening elements is at least partially inserted into the second element from the same pair,
• wherein the first element from each pair of complementary fastening elements comprises a protruding portion and a slot dividing the protruding portion into at least two segments, each segment being defined by at least one side wall of the segment, and the second element from each respective pair comprises a recessed portion defined by at least one side wall of the recessed portion and a partition extending into the recessed portion,
• wherein in each pair of complementary fastening elements the protruding portion is inserted into the recessed portion and the partition is inserted into the slot,
• wherein one element from each pair of complementary fastening elements comprises in the at least one side wall of the segment, or in the at least one side wall of the recessed portion, a protrusion, and another element from the same pair comprises in the at least one side wall of the segment, or in the at least one side wall of the recessed portion, a recess complementary in shape to the protrusion,
• wherein the protrusion and the recess connect the first and second elements from the pair by engaging the protrusion in the recess,
• wherein the partition of a first pair of the at least two pairs of complementary fastening elements has a different shape from the partition of a second pair of the at least two pairs of complementary fastening elements when viewed along a plane perpendicular to a direction of insertion of the partition into a corresponding slot and/or the partition of the first pair is rotated relative to the partition of the second pair about an axis parallel to the direction of insertion of the partition into the corresponding slot,
• wherein the slot of the first pair has a shape when viewed along the plane and/or rotation relative to the axis complementary to a shape when viewed along the plane and/or rotation relative to the axis of the partition of the first pair and non-complementary to a shape when viewed along the plane and/or rotation relative to the axis of the partition of the second pair.