For ease of processing during wave or reflow soldering, connectors can be delivered with snap-clips. Compared to screwing or riveting, these clips offer a fast and efficient fixing system, and provide additional mechanical protection after soldering is completed. In a typical rack based application, multiple daughter cards may be populated with identical DIN 41 612 connectors. To prevent accidental plugging into the wrong slot within the rack, connectors can be coded, which provides safe protection to the entire system. Options for coding include a strip fitted to the connector body into which coding keys are inserted, available for types D and E. This allows over 900 coding variations. For type F, H, and MH 24 plus 7, a code key can be inserted into the wall of the female connector, with the corresponding male slot broken out on the connector wall.