ARCADIA, Calif. — Striking United Launch Alliance employees will return to work after voting May 19 to accept a revised contract, ending a two-week strike.

Nearly 600 members of the Machinists Union, who had been on strike after rejecting ULA’s initial contract offer May 6, voted May 19 to accept a revised deal, according to statements from the union and company. The union did not disclose the margin by which the union accepted the revised contract.

“The ratification of a new agreement is a huge win not only for Machinists Union families at United Launch Alliance, but also for the U.S. space program and the local economies in Alabama, California, and Florida,” the union said in a May 19 statement announcing the contract vote. “The U.S. space program keeps our country safe and this new contract with United Launch Alliance will continue to set the standard in the U.S. space industry.”

The revised contract addressed several issues that led the union to reject the previous offer. The four-year contract — one year longer than the original offer — includes increased pay raises. It includes changes in “directed travel” for union employees, including additional hourly pay for those sent from ULA’s Decatur, Alabama, factory to launch sites in Florida or California. The revised agreement also makes changes to insurance and pension provisions.

“We are pleased that the IAM represented employees have ratified this agreement that is so critical to continuing ULA’s success,” Tory Bruno, president and chief executive of ULA, said in a May 19 statement, referring to the union by its formal name of the International Association of Machinists and Aerospace Workers, or IAM. “We believe this contract will help secure our place as the go-to provider for launching people and one-of-a-kind payloads into space well into the future.”

With the contract approved, union members will return to work May 21. The two-week strike did not affect any ULA missions, as its next launch, of NASA’s Parker Solar Probe on a Delta 4 Heavy, is not scheduled until the end of July.