IEC 63171-5:2022 refers to International Standards for test and measurement, environmental testing as well as solderless connections. This part of IEC 63171 describes 2-way shielded or unshielded circular connectors with IP65/IP67 M8 or M12 locking, typically used for balanced single-pair data transmission with frequencies up to 600 MHz and with current-carrying capacity up to 4 A, for use in areas with harsh environmental conditions. These connectors consist of fixed and free connectors, either rewirable or non-rewirable. Male connectors have square cross-section contacts.