About 21,000 Boeing engineers and technical workers are voting on a new four-year contract recently negotiated by the Boeing Co. and the Society of Professional Engineering Employees in Aerospace (SPEEA).

The ballots were mailed Monday, according to SPEEA spokesman Bill Dugovich. The ballots will be counted on Dec. 1 and the results will be known that evening.

SPEEA members will vote on two matters, one to approve the contract and one to authorize a strike. The two questions are typically the way a contract vote is presented to members.

SPEEA negotiators and leadership have recommended that union members approve the contract. There are about 3,400 SPEEA members who work at Boeing’s facilities in Renton.

The issues for the engineers and technical workers centered around wages, benefits and job outsourcing, similar issues that went unresolved in contract negotiations between Boeing and the Machinists, leading to a roughly two-month strike.

Also an issue was what Dugovich described as Boeing’s two-year effort to remove the engineers in Utah from the bargaining unit. The engineers rejected that effort, he said.

Two contracts were involved in the negotiations. The first covers 14,000 engineers in the SPEEA Professional Bargaining Unit. The second contract covers 7,000 technical workers in the union’s Technical Bargaining Unit, according to the two sides.

While the majority of workers are in the Puget Sound region, the contracts cover employees in Oregon, Utah and California.

Both contracts expire Dec. 1. The negotiations started Oct. 29.

The new four-year contract would expire on Oct. 12, 2012.