General Dynamics Electric Boat has been awarded a $19 million contract modification for the continued development of the Virginia Payload Module, or VPM, the company said Tuesday.

The funds will be used to procure two VPM pre-production setups to support the manufacturing start of the payload tubes, the company said in a statement.

The VPM will comprise four large-diameter payload tubes in a new hull section to be inserted in Virginia-class submarines.

The modification brings the value of the overall Virginia-class Lead Yard Services contract, initially awarded in 2010, to $1.46 billion.

The Virginia class is the U.S. Navy's next-generation attack boat, replacing the Los Angeles-class submarines as they retire.