The hardtop 2016 Smart ForTwo underwent a full redesign, but the convertible version will keep the old body style for another model year.

Buyers wanting the updated Smart platform as well as a convertible top will have to wait until the 2017 Smart ForTwo Cabrio bows next year.

That car made its official debut at the 2015 Frankfurt Auto Show, and will go on sale in the U.S. by summer 2016.

DON'T MISS: 2016 Smart ForTwo: First Drive Of All-New Two-Seat Minicar

The ForTwo Cabrio features a "Tritop" roof that can be configured three ways: fully open, fully closed, and partially open, like a big sunroof.

The roof can be opened while driving (presumably at low speeds), and takes 12 seconds to retract. The driver can also control operation from outside the car using the key fob.

While the mechanism is automatic, fully opening the roof requires removing side bars, which stow on the inside of the tailgate.

2017 Smart ForTwo Cabrio, 2015 Frankfurt Auto Show

2017 Smart ForTwo Cabrio, 2015 Frankfurt Auto Show

As with most convertibles, the ForTwo Cabrio required extra structural reinforcement to account for the loss of a fixed roof.

Changes include a large steel cross under the vehicle, a pair of torsional bulkheads on the underside at the front and rear, and inner tubes in the A-pillars made from high-strength steel.

ALSO SEE: 2016 Smart ForTwo: What You Should Know About All-New Minicar (Jul 2014)

All of this likely adds weight compared to the coupe, but torsional strength is also increased 15 percent compared to the previous-generation convertible.

While buyers in other markets will get multiple three-cylinder gasoline engine options, only one will be offered in the U.S.

This 0.9-liter turbocharged engine produces 89 horsepower and 100 pound-feet of torque.

2017 Smart ForTwo Cabrio, 2015 Frankfurt Auto Show

2017 Smart ForTwo Cabrio, 2015 Frankfurt Auto Show

Buyers will get to choose between five-speed manual and six-speed dual-clutch transmissions, as well as four trim levels: Pure, Passion, Prime, and Proxy.

The ForTwo Cabrio will also be offered with several electronic driver aids, including a collision warning system.

MORE: Five Convertibles With High Gas Mileage: Enjoying Summer Efficiently

The 2017 Smart ForTwo Cabrio goes on sale in Europe in February, and will reach the U.S. by early summer.

For more 2015 Frankfurt Auto Show coverage, head over to our show news hub.

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