Atera SIGNO AS silver aero-profile bars no. AR7391

Atera's SIGNO AS aluminium cross bars are sold as a complete package, ready to fit.

We've seen their development over several years and know that they've been refined and refined, with a lot of wind tunnel testing, to achieve optimum efficiency - low noise and low drag - despite not having any rubber infill in the slotted channel.

Keeping this channel open was the challenge that Atera set their design team. Other aerofoil bars (apart from Whispbar) are only quiet if rubber strips are pushed into their 'T-track slots', rubber which needs to be cut into sections and placed between, for example, bike carriers, and then more rubber added when the bike carriers are removed. You want to leave your bars on your car ready for the next time you go biking, and just slide or drop the bike carriers into them without any need to fit and remove rubber strips? Is speed and ease of use important? Of course it is, which is why the engineering behind these bars is really very clever indeed.

What's the science behind this success? See the final picture above. In summary, the WindBarrier strip creates small swirls which form an AirCushion across the surface of the T-track slot, preventing the development of wind noise whatever the driving speed. The design of the ShapeBreak trailing edge also controls the airflow, improving roof bar stability and reducing the downward force.

Other features:

• The quality of the aluminium and the plastic mouldings, makes these bars a pleasure to handle
• There's real attention to detail. For example, the slot under the bar, which the feet slide in, also needs to be filled to reduce noise; there's an automatic adjusting cover for the part of the slot behind the feet
• The recessed lock, with its special tensioning key, is intrinsically much more secure than using a standard type of external lock and key
• The end caps slide down to allow access to the T-track slots - a very crisp and smart solution
• The clamping jaws have a special rubber lining that provides excellent friction grip, yet doesn't leave any residue even in very hot weather
• Weight: 4.5kg
• Load carrying weight: 100kg but please be guided by the maximum permitted roof loading limit of your vehicle!
• Roof bar dimensions: 78mm wide by 27mm deep
• The 'T-track' slots use 20mm x 20mm adapters - the same as CRUZ, Thule and Whispbar aluminium bars
• Locks are included
• 5 year guarantee
• Made in Germany

Colleagues here who've had the opportunity to use these aero-profile bars to carry their bike racks are very confident that Atera have nailed it!

Most of Atera's roof bars and accessories business is with the Original Equipment market, i.e. direct to the car manufacturers, where major customers include Audi, BMW, Daewoo, Chrysler, Fiat, Honda, Hyundai, Mitsubishi, Mercedes, Opel, Porsche, Smart, Subaru, Suzuki, Vauxhall and Volkswagen. Atera’s reputation therefore speaks for itself and, (probably needless to say), their products are manufactured, city crash tested, TÜV certified and quality approved to the highest international standards including DIN ISO 1135, DIN ISO 75302, and IAF ISO 14001:2004.

The aim of this note is to persuade you that kayaks should always be tied to the carrying vehicle at both bow and stern.

Untied kayaks have, in our experience, the greatest potential for a roof bar or kayak carrier failure. The massive forces that untied kayaks can generate have even been known to snap roof bar fixing bolts with the result that a complete assembly of roof bars and kayaks has ended up on the road. We know that this has happened with almost every brand of roof bar, and regardless of whether the kayaks are on a special carrier or just strapped to the bars.

You need to fix bow and stern lines, probably using the front and rear screw-in towing eyes to get strong and accessible fixing points on the vehicle. Kayak shops should be able to provide suitable 'paracord' for this purpose. It is cheap and readily available online. Alternatively, Thule makes the QuickDraw 838 which we have listed together with every kayak carrier we sell.

Please note that kayaks should be strapped to the roof bars, or to kayak carriers, using straps that are suitable for the purpose, e.g. 25mm polypropylene straps with strong buckles. Bungee cords must never be used.

Please also note that all roof bar instructions point out the dangers of carrying unsecured long items, as of course do all kayak carrier instructions.

If you tie down your kayaks you almost certainly won't experience a product failure. If you don't you may or may not get away with it. If there is a disaster and the kayaks end up on the road, separated from the vehicle, then you were not using tie downs and you have subjected the roof bars to forces for which they were not designed. The costs of sorting this out are yours, not ours, and you may also have difficulties with your insurers.

We're sorry to be so firm about this, but "things coming off the tops of cars" is the stuff of nightmares, and we want to do all we can to prevent accidents of this sort from happening.

Delivery charges and arrangements:

We charge a contribution towards delivery costs, depending on what you order, where you live, and how quickly you want the goods.

These are our standard charges; there are usually surcharges for all offshore destinations and some remote postcodes - for details please see our delivery information page.

Delivery of other items

Delivery times

Delivery times are calculated in working days (Monday to Friday, excluding Bank holidays).

Cut-off times for Express Delivery orders
Express Delivery orders placed before before the cut-off times shown below will usually be desptached on the date of order. Express Delivery orders placed after these cut-off times will be despatched the next working day.

Delivery FAQs

When will my order arrive?
There are no deliveries on Saturdays, Sundays or Bank Holidays, except for postable items where Royal Mail has a Saturday delivery. Express Delivery orders placed on a Friday (before 1pm) should be delivered on the Monday or Tuesday, Express Delivery orders placed on a Saturday or Sunday should be delivered on the Tuesday or Wednesday. The arrangements for Very Heavy Items are different and are shown above.

What about Next Working Day delivery?
Most Express delivery orders will arrive on the next working day, if the order is placed before the cut-off time (see above). Some will arrive on the second working day if there has been a "split-delivery". So-called “split deliveries” happen when the couriers do not have enough trailer space for everything that should be moved around the UK, so they will load what they can and leave the rest for the next trailer.

Is my delivery day guaranteed?
No retailer or courier company can ever "guarantee" a Next Working Day delivery. As well as split deliveries, all courier companies occasionally have the same transport problems as can happen to everyone else, including snow blocked roads, closed roads, traffic jams, mechanical breakdown, an inability to find the delivery address, or to gain access to it if, for example, it's in a block of flats. We work with some of the best couriers in the business, and overall they provide an outstanding service.

Do I need to be at home?
We are very flexible with our deliveries and will aim to deliver to an address which suits you – this does not need to be your home address. Goods can usually be left without signature - we prefer this with roof boxes. There's a "Special Delivery Instructions" box in the checkout area where we'll ask you to choose a typical instruction and then amend it to suit your particular requirements.

Payment options:

We take the following cards, and also PayPal. Please note that the entry on your card statement will be from "The Roof Box Company".

Secure payments

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