The 2013 Ford Flex SEL is a distinctive and spacious full-size crossover SUV known for its boxy, wagon-like styling and comfortable ride. Here's a description of the SEL trim:

Key Characteristics:

Unique Exterior Design: The Flex stands out with its flat roof, straight lines, and available contrasting roof colors, giving it a retro yet modern look. The SEL trim typically features 18-inch painted aluminum wheels, body-colored door handles and mirrors, and chrome accents on the grille and liftgate.

Spacious Interior: A key selling point of the Flex is its roomy cabin with standard three-row seating for seven passengers. The second and third rows fold flat, providing a substantial cargo area.
 
SEL Trim Features: The SEL builds upon the base SE trim with several desirable upgrades:
Heated front seats: A welcome comfort feature, especially in colder climates.
Power-adjustable driver and front-passenger seats: Offering more customization for optimal driving and passenger comfort. The driver's seat typically has 10-way power adjustability including lumbar support.
Dual-zone automatic climate control: Allows the driver and front passenger to set their preferred temperatures. Rear air conditioning vents are also standard to keep all passengers comfortable.
MyFord Touch infotainment system: This system includes an 8-inch touchscreen display, enhanced voice control, and customizable menus. It integrates audio, climate control, phone, and available navigation functions. Note that this system was known to have a learning curve and could be divisive among users.  
Upgraded SYNC system: Provides enhanced connectivity features, including voice-activated controls for phone and entertainment.
Leather-wrapped steering wheel: Adds a touch of refinement and better grip.
Rear parking sensors: Aid in maneuvering and parking in tight spaces.
SiriusXM Satellite Radio: Offers a wide variety of audio entertainment (subscription required).  
Six-speaker audio system: Provides standard audio output.

Engine and Performance: The 2013 Flex SEL comes standard with a 3.5-liter V6 engine producing around 287 horsepower and 254 lb-ft of torque. It's paired with a six-speed automatic transmission. Front-wheel drive (FWD) is standard
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Ride and Handling: The Flex prioritizes a comfortable and smooth ride, making it well-suited for family road trips. While not sporty, it offers decent handling for its size and feels planted on the road.

Safety Features: Standard safety features on the 2013 Flex SEL include antilock disc brakes, stability and traction control, front side airbags, and side curtain airbags for all three rows.  

In Summary:

The 2013 Ford Flex SEL is a practical and distinctive full-size crossover that offers ample passenger and cargo space, a comfortable ride, and a good set of standard features. While its MyFord Touch system had its critics, the overall package of space, comfort, and unique styling made the Flex SEL a solid option for families seeking something different from the traditional SUV or minivan.