The system for sealing subsea equipment includes a port tube, having a test port hole and a curved slot, a test port plug mounted in the test port hole, an insert body having an insertion tip portion, a middle sealing portion, and a base portion, an insert stem engaged to the base portion, a top cap engaged to the insert body, and a sealing device mounted around the insert body and in sealing engagement with the port tube. A locked configuration corresponds to a locking arm of the top cap at a terminal end of the curved slot. A set configuration corresponds to compression of the sealing device by actuation of the insert body by the plug stem. The sealing device aligns with the test port plug in the set configuration so as to allow verification of sealing engagement of each seal ring and the port tube.