Abstract: A connector is provided for use with an orifice with internally-retained cap. Unlike conventional connectors, the invention provides a passage for the restraint that retains the associated cap internal to the orifice and a fitting which engages the method used for the cap to seal the orifice. As a result the invention may be used to safely engage any neck, whether threaded, keyed or otherwise sealable, of any vessel, whether by threading, being keyed, or having a press-fit connection. The connector may also be eccentrically constructed so that it may be aligned nonconcentrically to the orifice.