The doors of the trailer opened to reveal a black Tesla Roadster, Tesla Motors' very first production car. Chairman Elon Musk got behind the wheel and steered as employees rolled the car

"This is the first production electric car on the road for decades," said Musk, co-founder of PayPal and SpaceX, to a crowd of employees and reporters. "The EV1 and Rav4 weren't for sale, but were for lease. The first production Roadster is a huge accomplishment for the company. Thanks for making it."

After the cheers and applause died down, Musk referred to rumors about the number of cars Tesla will build.

"I want to be very clear; we are going to put thousands of vehicles out there," he said.

Aside from the Roadster, Tesla plans to make 20,000 to 30,000 of its next model, a family car code-named "WhiteStar," per year, Musk said.

"Beyond that is Model 3, and we're going to do parallel investing, so we're not going to wait for Model 2 to work on Model 3," he added. Musk didn't disclose any additional details about the third model.

"Until we see every car on the road -- or essentially every car on the road except for [unique] cars in museums -- we will not stop," Musk said, bringing more applause. "This is the beginning of the beginning."

Then Tesla technicians raised the car and got to work, moving the suspension-control arm, tying back some electrical components and running through a quality check to make way for the installation of the battery pack -- altogether a two-hour process.

Employees watched, as they have with every Tesla prototype that has arrived, each in a different color until now.

"It's a huge deal," said Colette Niazmand, operations manager of sales, marketing and service at Tesla, who has been with the company for three and a half years and saw the company's first "mule" -- a Tesla engine in a Lotus body -- being built. "We've known we're a real car company and forward-thinking, but the P1 signifies to the world that we're a real car company and that we're going to change the world."

While the company isn't making any promises, Musk said he hopes more production cars will be ready sooner than expected.

"This really must be an [exciting] day for employees at Tesla," Musk said. "We didn't really know what would happen -- if it would miss a train or if we'd open the box and it would be broken.

The company originally expected the first production Roadster to arrive Tuesday, but a missed connection in Amsterdam delayed the arrival (see Missed Flight Gives Tesla Another Headache).

As previously announced, Musk's car has an interim transmission that will put the acceleration at 0 to 60 in 5.7 seconds instead of "about four" for now.

But all the "early production" Roadsters, including this first one, will be upgraded to a production transmission system for free, Niazmand said. Tesla isn't yet able to disclose how much the upgrades will cost the company, since the cost will depend on volume, she said.

Darryl Siry, vice president of sales and marketing, previously said the company would try to limit the volume of the "early production" cars with the interim transmissions (see Tesla Announces New Transmission).

Greentech Media also interviewed Tesla CEO Ze'ev Drori during the event. Look for a Q&A soon.