Abstract: An apparatus for connecting a first wellsite tube to a second wellsite tube includes a collar configured to engage with outer conduits of the first and second wellsite tubes. A coupling is disposed inside the collar and includes a first end axially disposed from a second end. A first structure is configured to provide sliding engagement between the first end of the coupling and an inner conduit of the first wellsite tube. A second structure is configured to provide threaded engagement between the second end of the coupling and an inner conduit of the second wellsite tube. A plurality of radially extending ribs are disposed between the opposing ends of the collar and support the coupling inside the collar.