Shuttle drivers working for five tech giants in the Silicon Valley voted in favor of the joining the Teamsters union on Friday.

Teamsters is a labor union in the United States representing blue-collar and professional workers in both the public and private sectors. It currently has 1.4 million members with different jobs.

First to join Teamsters last year were the drivers of Facebook's shuttles. The union closed a contract to raise their pay by $6.50 per hour, from $18 to $24.50, for over three years. Drivers are also given the option to decline to work on split shifts if they feel that they will not have enough rest in between shifts.

On Friday, 158 full-time and part-time drivers working for Compass Transportation that transports workers for Apple, Yahoo, eBay, Zynga, Genentech, and Amtrak voted to join Teamsters. The tally was 104-38 in favor of the union, according to The Wall Street Journal.

"This is another step, in addition to the Facebook drivers, for the workers who support the tech industry to move forward toward decent wages, affordable health care and a pension for the future," Rome Aloise, secretary-treasurer of Teamsters Local 853, said in a statement.

Compass refused to comment on its drivers' decision to unionize. But prior to the voting, it said that their drivers are already well-paid.

"Compass is committed to rewarding its employees and drivers and providing competitive wages and benefits as compared to other employers in our industry and in our area," Compass Senior Vice President Bryan O'Connell told the Silicon Valley Business Journal,

Tracy Kelly, one of the shuttle drivers, is happy with the voting result. He is hoping to close the same deal that the union had for the Facebook shuttle drivers with Loop Transportation.

"It's about having sick time. It's having vacation time. It's better planning the split shifts," he said. "It's about having a place with a secure future going forward with benefits and the ability to take care of a family member who gets sick."