Light-topped Havnby car mattress with gray sides and shaped edges, isolated on a white background.
Full-width Havnby mattress with two teal pillows installed in the cargo area of a Subaru Outback.
Two people cooking at a campsite behind a Subaru Outback with a Havnby mattress in the cargo area.
Person sleeping flat on a Havnby mattress in the cargo area of a Subaru Outback.
Teal pillow supporting the gap behind a Havnby mattress inside a Subaru Outback.
Close-up of a Havnby mattress built-in pump panel with USB-C input, indicator light, dial and vent.
Hand pressing a Havnby car mattress beside a window showing its internal layers.
Hands rolling up a gray Havnby mattress in a vehicle’s cargo area.
Gray Havnby mattress carrying bag in the cargo area of a Subaru Outback with the rear seats upright.
Person and dog relaxing on a Havnby mattress under the illuminated rear hatch, with another person beside the vehicle.
Person sitting on a Havnby mattress at the open rear hatch of a Subaru Outback, with another person standing nearby.
Person and dog resting on a Havnby mattress in the open cargo area of a Subaru Outback in a forest.
Two people relaxing on a Havnby mattress in the illuminated cargo area of a Subaru Outback at dusk.

FlatCore Hybrid Support Mattress for Subaru Outback

Levels the sleeping surface without a separate platform build.

Sale price$529.00
60-Day Sleep Trial
3-Year Warranty

Havnby FlatCore Hybrid Support Mattress for Subaru Outback creates a flatter, more supportive sleep space for Subaru Outback.

  • Vehicle-specific fit: Shaped for Subaru Outback.
  • Flatter sleep surface: Helps reduce slopes, gaps, and height changes.
  • Air-and-foam support: Combines structure with cushioned comfort.
  • Built-in pump: Inflates quickly without a separate pump.
  • No platform needed: Adds support without a permanent camper build.
1 Mattress ≈ 2–3 Hotel Nights Near A National Park

A full-width Subaru Outback sleep system levels the uneven cargo area, bridges the space behind the front seats, and preserves more headroom than a raised platform.

Is FlatCore Right for Your Outback?

Made for Outback owners who want a flatter bed without a platform

Folding the seats creates plenty of length, but not a truly finished bed. FlatCore levels the uneven cargo area, bridges the space behind the front seats, and preserves more headroom than a raised platform.

When the Folded Floor Still Isn’t Flat

“The mattress levels the floor and sleep is great.”

— Outback owner, r/Subaru_Outback

When the Seat Gap Cuts Into Your Sleep Space

“I’m looking for something to fill the seat gap so we can have the full amount of room to stretch out.”

— 2017 Outback owner, r/Subaru_Outback

When Headroom Matters More Than Storage

“I like having headroom, so I decided against a platform with drawers underneath me while sleeping.”

— Outback owner, r/Subaru_Outback

Core Design Details

Key Features

Person lying on a Havnby FlatCore mattress with a teal pillow in the cargo area of a Subaru Outback.

Outback-Specific Leveling Support

The Outback’s rear seats fold down, but the cargo area still slopes and changes height. FlatCore’s shaped air base levels the uneven surface and supports the space behind the front seats, without plywood, storage bins, or a permanent build.

Two people reclining on a Havnby mattress with teal pillows inside a Subaru Outback.

Designed Around the Outback’s Full Cabin Width

FlatCore extends toward the Outback’s side armrests, turning the space along both sides of the cargo area into part of the sleep surface. The result is a 53.1" / 135 cm-wide sleeping area with more room for two adults.

Hands fastening the compression straps around a rolled Havnby mattress in a vehicle’s cargo area.

Foam Comfort with Adjustable Air Support

Air provides the structure while foam cushions your shoulders, hips, and other pressure points. Together, they create a steadier, more supportive surface with less of the bounce you expect from a basic air mattress.

Close-up of a Havnby mattress built-in pump panel with USB-C input, indicator light, dial and vent.

Set up and Pack Down with the Built-in Pump

The rechargeable built-in pump inflates FlatCore in approximately 73 seconds. No separate pump to carry, connect, or keep track of when you arrive after dark.

Close-up of the Havnby logo printed on the light-colored surface of a FlatCore mattress.

Soft-Touch TPU Surface

Unlike the slick, plastic feel common with PVC air mattresses, FlatCore uses TPU-laminated fabric for a softer, more mattress-like surface with less noticeable odor.

A woman loading a dark gray Havnby duffel bag into the open trunk of a car outdoors.

Ultra-Packable Design

When the trip is over, the built-in pump compresses FlatCore in approximately 81 seconds. It rolls into its 28.3-by-15.7-inch carry bag, leaving the Outback ready for passengers, groceries, and everyday cargo.

Additional Benefits

Two dogs sitting beside a gray Havnby mattress carrying bag in the cargo area of a Subaru Outback.

Built-In Snaps Keep It Rolled

Side snap tabs hold the compressed mattress together while you place it in the carry bag, keeping pack-down controlled instead of letting the roll spring open.

Two people sleeping on a Havnby mattress in the cargo area of a Subaru Outback.

Full-Width Comfort for Two

The 53.1-inch-wide surface creates a shared sleeping space for two adults and supports up to 661 pounds combined. Cozy enough for the Outback, supportive enough for a full night outside.

Two people cooking beside a campfire behind a Subaru Outback with a Havnby mattress set up inside.

A Better Place to Recover Between Miles

Stretch out after a long drive, recover at the trailhead, or settle in before an early start. FlatCore turns the parked Outback into a comfortable place to slow down and recharge before the next part of the trip.

Size On

Dimension diagram of the Havnby FlatCore mattress for Subaru Outback, with top and side views.
A dark gray cylindrical duffel bag with top handles and the white 'Havnby' logo printed on the front, shown against a plain white background.

PACKED SIZE

28.3" × 15.7"

FlatCore_CloudCore_Battery

INFLATE TIME

73 Seconds

Specifications

Fit
Subaru Outback
Layout
Full-Width
Mattress size
74.0" × 53.1" × 5.5" / 1880 × 1350 × 140 mm
Packed size
28.3" × 15.7"
Inflation time
73 seconds
Compression time
81 seconds

What real owners are saying

Ali

2025 Toyota RAV4 XLE Owner

"Setup took two minutes, pump included, module charges over USB-C. Fit the RAV4 perfectly with no platform needed, and slept two of us by the lake like a real mattress."

Person reclining on a light-colored Havnby mattress in the cargo area of a Toyota RAV4.

David L.

2022 Toyota RAV4 Owner

"Took the whole family camping in the RAV4 for the first time. Kids were asleep before we finished making dinner, and nobody complained about the ground once."

Jordan M.

2023 Tesla Model Y Owner

"Fits the load floor perfectly, no gaps, no sliding. Woke up in the Sierras on Sunday feeling more rested than I expected from a car."

Mike B.

2020 Ford F-150 Owner

"Twelve hour shifts two hours from any job site. Now I lay the seats down, sleep in the truck, and I am back at it in the morning without the drive home."

Ingrid S.

2024 Model 3 Owner

"Drove through Jotunheimen after a week with no plans. The fit was exact, and the material held up through four nights without any issues."

Life with Havnby

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