The F-3100 Series of Standard Bulkhead Connectors from Air Logic have two bulkhead connector variants, one reducing, and one straight. These are used to connect tubings with 1/16-inch, 1/8-inch, or .170-inch I.D's. However, there is no locking nuts included. These units are available in white or black nylon, or gray polypropylene. The polypropylene units are used for operations that require more chemically resistant connectors.