Which feature of the Molex connector prevents improper insertion into a port?

The feature of the Molex connector that prevents improper insertion into a port is keying. Keying refers to the design of the connector that includes specific shapes or arrangements of pins and slots that allow it to fit into its corresponding port in only one orientation. This is particularly important for ensuring that electrical connections are made correctly, which prevents damage to the device and ensures reliable operation.

Other features, such as color coding, size variations, and the materials used, can aid in identification and compatibility but do not specifically prevent incorrect insertion. Color coding may help users easily identify different connectors or wires, while size variations can ensure that connectors are not interchangeable with incompatible ports. Materials used in connectors are primarily focused on durability and electrical conductivity, rather than on guiding correct insertion. Keying is specifically engineered to achieve proper alignment and connectivity, making it the correct feature associated with preventing improper insertion.