Until the assassination of John F. Kennedy, presidential state cars frequently allowed the president to ride uncovered and exposed to the public.

[9] The Sunshine Special (so named because the top was frequently open)[12] became the president's best-known automobile, the very first to be built to Secret Service specifications, and the first to be leased rather than bought.

[9] Built on the chassis of the Lincoln K series,[12] the Sunshine Special has a 160-inch (4,100 mm) wheelbase, room for 10 passengers, rear suicide doors, heavy-duty suspension, two side-mounted spare tires, and standing platforms attached to the exterior to accommodate Secret Service agents.

In 1942, after the attack on Pearl Harbor, the car underwent the addition of armor, one-inch (25 mm) bulletproof glass, "metal-clad flat-proof inner tubes, a radio transceiver, a siren, red warning lights, and a compartment for submachine guns."

"[14] In 1954, President Dwight D. Eisenhower had the Cosmopolitan convertible fitted with a Plexiglas roof that became known as the "Bubble-top"; it remained in presidential service until 1965,[9] and has approximately 105,942 miles (170,497 km) on the odometer.

[15] President John F. Kennedy's 1961 Lincoln Continental was originally a stock car, built in Wixom, Michigan, and retailing for $7,347 (equivalent to $74,910 in 2023).

[16] The dark-blue car included a "heavy-duty heater and air conditioner, a pair of radiotelephones, a fire extinguisher, a first-aid kit, and a siren.

[16] The exterior featured retractable standing platforms and handles for Secret Service agents, and flashing red lights recessed into the bumper.

Unique to the X-100 were three removable roofs (made of fabric, lightweight metal, and transparent plastic) and a hydraulic lift that could raise the rear cushion 10+1⁄2 inches (270 mm) off the floor.

Hess and Eisenhardt, the Secret Service, the United States Army Materials and Mechanics Research Center, PPG Industries, and Ford engineers all collaborated to strip the limousine and make substantial improvements.

[9] Despite successive presidential state cars being built and delivered to the White House, the X-100 continued to be occasionally used by Presidents Lyndon B. Johnson, Richard Nixon, Gerald Ford, and Jimmy Carter until it was retired from service in early 1977.

[18] President Johnson preferred white convertibles, but "concerns for protocol and safety" had him receiving a black 1967 Lincoln Continental as his state car.

The fully loaded automobile had a 460-cubic-inch (7.5 L), 214-horsepower (160 kW) V8 engine; external microphones to allow occupants to hear outside noises; full armor plate; bulletproof glass; and racks for the Secret Service to store submachine guns.

[21] By 1974, the car was typically transported by the United States Air Force in a Lockheed C-141 Starlifter cargo plane at an hourly jet fuel cost of 1,800 US gallons (6,800 L; 1,500 imp gal).

[9] During the March 1981 attempted assassination of Ronald Reagan, the car was hit by the last two of six gunshots, which respectively damaged the bulletproof window of the right rear passenger's door, and ricocheted off the back-right quarter panel before striking the president.

It featured armor and bulletproof glass (2+3⁄8 inches [60 mm] thick),[12] and was described as "distinctively styled, with a raised roof and a large rear greenhouse."

Museum curator Christine Mouw noted that they can "dust the outside of the car, but if we needed to get inside it, we would have to contact the regional Secret Service office".

[6] CNN interviewed Joe Funk, a former Secret Service agent and driver of Clinton's presidential state car during part of his tenure.

[12] The additional armor and amenities that were added to the state car by the Secret Service taxed previous presidential limousines beyond their limits, resulting in failing transmissions and short-lived brakes.

The George W. Bush state car was instead designed from the ground-up by "an R&D arm of General Motors in Detroit" to meet Secret Service specifications.

[12] Confirmed accessories include "an integrated 10-disc CD changer, a foldaway desktop[,] and reclining rear seats with massaging, adaptive cushions.

Anton Goodwin of CNET's Road/Show blog noted that speculation was that the presidential state car was based on the GMC Topkick platform.

[25] This presidential state car was also believed to be much heavier than its predecessor as it is equipped with Goodyear Regional RHS tires that are usually reserved for medium- and heavy-duty trucks; speculated weights range from 15,000 to 20,000 pounds (6,800 to 9,100 kg).

"[10] The curator of The Henry Ford told The Dallas Morning News that President Obama's state car was "a tank with a Cadillac badge.

The switch came after the D.C. city council petitioned President Obama to use the plates on his motorcade, which would be seen by millions of people as he headed down Pennsylvania Avenue for his second inauguration.

[32] After prototypes of the new model were seen driven on public roads wrapped in monochromatic multi-scale camouflage, Cadillac confirmed to Fox News that "We've completed our task and we've handed over the vehicle to the customer".

[2] Under President Obama they constituted 30 other vehicles,[3] including police cars to lead the motorcade and clear the streets; sport utility vehicles to carry the United States Secret Service detail, electronic countermeasures, key staff, a Secret Service Counter Assault Team, "hazardous-materials-mitigation" personnel and equipment, and White House Communications Agency personnel; press vans; an ambulance; and more.