Nearly 2,000 AC Transit bus drivers, mechanics, dispatchers, clerical workers and others are voting Friday on their third labor agreement in six months.

Amalgamated Transit Union Local 192 members rejected the past two deals between union negotiators and the transit agency, reportedly over provisions that required them to pay more for their pensions and health insurance.

Details of the third tentative agreement reached last week have not been publicly released.

Voting was scheduled to take place in multiple locations through early evening. The union has not said when it will announce the results.