Our spy photographers have hit the motherload as they've managed to capture a handful of BMWs at a testing facility in Germany.

While we can see several different models in the parking lot, we're primarily interested in the 4-Series Convertible which is inching closer to production.

Set to go on sale later this year, the convertible closely echoes the 4-Series Coupe but is distinguished by a lower beltline, a flatter trunk and a three-piece folding hardtop. The roof continues to be aesthetically challenged but should appeal to buyers in colder climates.

Engine options will carryover from the coupe so expect choices to include a turbocharged 2.0-liter four-cylinder with 240 bhp (179 kW) and 255 lb-ft (345 Nm) of torque as well as a 3.0-liter six-cylinder engine with 300 bhp (224 kW) and 300 lb-ft (406 Nm) of torque. Regardless of which engine is selected, it can be paired to a six-speed manual or an eight-speed automatic.

The BMW 4-Series Convertible is expected to go into production in November, so expect an official unveiling in the coming months.

Gallery: 2014 BMW 4-Series Convertible spied with less disguise

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