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Thule Sonic XL Roof Box


    Thule Sonic XL Roof Box

    Slicing through the air like a hot knife through butter, the new Thule Sonic XL roof box features a patented aerodynamic design.

    • $629.95

    Item # 850920

    REI Members get back an estimated $ 63.00 on this item as part of their annual member refund.

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    Product size and color
    * Color/Size is out of stock but can be backordered.
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    • Front of cargo box features a patented AeroNose design that is pointed so box cuts through the air, helping to reduce drag and noise
    • Rear of cargo box also features a patented rear-angled base design, helping to maximize trunk and hatch clearance
    • Mounting system clicks when you reach the optimal hold, so you'll be on the road in seconds; can be mounted on square and round crossbars and most factory racks (see Fit List)
    • Patented, dual-side openings let you access your gear from either side of the box
    • Locking system features an external lock-assist knob that is easy to use; built-in safety feature means the key can only be removed when the box is fully closed
    • User-friendly locking system includes an oversize key; a lock is located on each side of the box, and each one comes with 2 keys
    • Thule Sonic XL roof box holds 6 - 8 pairs or skis or 4 - 6 snowboards

    Thule Racks

    Please note: Thule products cannot be shipped to Canadian addresses.

    Made in USA.

    Item 850920

    An oversize shipping charge of $160 applies to this item (plus regular shipping fees). Or ship it FREE to any REI store for pickup. Please allow up to two weeks for delivery.

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    Thule Sonic XL Roof Box Specs
    Best use
    Dual side
    481 liter
    29,376 cubic inches
    6-8 pairs
    4-6 boards
    89 inches
    34 inches
    16 inches
    47 pounds
    Box opening
    Gear capacity (L)
    Gear capacity (cu. in.)
    Ski load capacity
    Snowboard load capacity
    Internal straps
    One-handed opening
    Length (in.)
    Width (in.)
    Height (in.)

    Thule Sonic XL Roof Box

    Loading Ratings & Reviews...

    Rated 4.6667/5 based on 6 reviews
    Rated 4out of5
    by fromQuiet ride with lots of extra cargo! My wife, my cat and I needed extra cargo for an extended vacation three days of driving from home. We got the Thule Sonic XL for the car because that was the largest rooftop cargo box that would fit our Jeep Grand Cherokee without interfering with the rear hatch. We were very pleased while packing for the trip that the addition of the Sonic XL was going to make our trip's payload feasible. The added seventeen cubic feet really helps when lugging along all the extra clothing for a colder climate, two boxed flatscreen monitors, camera tripod, gifts and so many other essentials for our trip. This Thule made it possible to do this trip with all the stuff we wanted to bring and more! The last of the three days of travel was through heavy rain, but all the contents of the Thule were dry upon arrival. I'm glad there was someone to help us install it at our local REI. Remember to consider that if you do not install it in the parking lot of REI, you might not be able to get it home inside your car. Be sure to schedule an installation time with the REI you purchase it from if this is your first cargo box. Things will just go better that way. --Great about it: Ease of installation. All I needed to install the lock cylinders was a sharp pocket knife to cut out the plastic knockouts. Both sides of the cargo box and all four lockdown points of the crossbars have the same key because of how easy it is to change the cylinders after unlocking them. Also, the black, glossy finish of the Sonic XL Pro looked really good on my SUV. It looked like it really was part of the car. Also, there was almost no additional road noise on the interstates. I did use Thule's Aero Bars as my crossbars for this installation, BTW. Not so great about it: If you tighten the calipers without something for them to clamp onto, it might damage the torque limiting calipers which grab onto the roof rack's crossbars. Thule! Please design that better! Also, Thule's website is awful at describing what you need to purchase with your cargo box and even worse at showing how it all goes together onto your car. The included international cartoon instructions were even worse. This box did what I needed it to do at a reasonable price. I recommend it, but from all I have heard from others, the Yakima is also a quality product. Thanks again for the installation help, REI!
    Date published: 2013-10-16
    Rated 4out of5
    by fromSo far, so good We have a '11 Ford Explorer and a family of 5. The Sonic gives us room inside the vehicle to enjoy long trips. So far, the Sonic has been easy to install, use and store.
    Date published: 2013-07-26
    Rated 5out of5
    by from20% off with member's discount and easy install Staff helped me get it on my car - 2011 BMW X5 with raised rails and square bar Thule rack and fairing. It fit nicely, and seemed very quiet on the ride home, but I have not driven it "at speed" yet. I definitely prefer the black color over silver - glad they had the black in stock. The XXL would have fit on my X5, but seemed like overkill for my needs. The XL does not noticeably extend over the windshield when in place, and the tailgate lifts entirely.
    Date published: 2014-04-11
    Rated 5out of5
    by fromThule super box and rack. The Thule roof box saves room in the vehicle for more people and dogs. Locking mechanism is exceptional. attractive on my vehcle and easily accessed from either side. I would recommend this box to anyone. REI was an excellent plact to purchase this product. The sales person was very helpful, courteous and knowlegdable about the product. I am a happy camper.
    Date published: 2014-01-08
    Rated 5out of5
    by fromA great cargo box This is a great cargo carrier. The road noise is unnoticeable, mounting/dismounting is easy and it has a ton of space. My fuel economy dipped by about .5 mpg on my full size SUV. The locks are solid. And yes folks, the lid is somewhat flimsy. I frequently see this as a complaint for ALL cargo carriers. It is a weight trade off. Just don't open the lid like a brutish neandrethal and you'll be just fine. I highly recommend this unit.
    Date published: 2013-06-27
    Rated 5out of5
    by fromGreat extra storage! We recently made a road trip to SC which wouldn't be cramped in my XTerra SUV... But we would be traveling with my Mom and our 2 four legged friends! We purchased this carrier to make room in our SUV. It is super easy and quick to install. There was no vibration or movement noted during our trip. We hit some heavy rain/snow and not one drop found its way into the carrier! It did not make a noticeable impact on our fuel consumption. Thanks for a great product!!
    Date published: 2014-02-20

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