Abstract: The invention concerns a device for preventing leakage of electromagnetic radiation between a first (10) and a second (12) part. The first (10) and the second (12) parts are shaped to be arranged against each other such that a first gap (20) is formed between them. Furthermore, the first (10) and the second (12) parts are shaped to engage each other such that at least a second gap (30) is formed between them. The second gap (30) defines a second plane (32) which forms an angle (34) with the first plane (22) which is defined by the first gap (20). Furthermore, the second gap (30) has an extension such that it intersects the first plane (32). The second plane (32) also has an extension in a leakage direction (24) which is defined by the first gap (20).