Vacuum interface valves covered by this CID are intended for use in VCHT systems on new construction ships or as stock replacements for VIVs currently installed on existing ships. When acquiring VIVs for replacement purposes, the contracting activity must ensure that interface requirements are specified for inlet connections, outlet connections, and mounting feet (if used), which are compatible with the VIV being replaced to avoid the need for costly ship modifications. Acquisition for new construction allows for more latitude in VIV dimensions and interface requirements, enabling more suppliers to bid thereby increasing competition.