Now in General Release - The  Land Rover Discovery 1 and 2 Tough Touring Gutter mount roof rail is secured by 4 Gutter mounts each side as per Pics above - Running off a 1 piece gutter rail that extends the length of the Disco's roof. 
The Tough Touring can be ordered in an 'OUtfold' (For wide roof top tents)  - or 'INFOLD' as per majority of roof racks - where the of the rail is folded inwards to look good.. (The GUNMETAL GREY DISCO IS RUNNING INFOLD and The SILVER ONE is OUTFOLD)

For OUTWARD FOLDED RAILS: Plank Lengths on the rack are 1550mm WIDE as standard ((ID up to 1350)
FOR INWARD FOLDED RAILS OPTION - Plank Lengths are 1400wide standard (ID 1220 )
Either Option has a combination of Single or Double Planks at each end and Single Planks in Centre provide a super solid and LOW mount platform ... Up to 9 Planks in total can be added. (4 are included in the Standard RACK KIT)

Double Planks are To be used at Each end in the event of wishing to run stand alone Pole less awning and RTT combinations. The Disco is a Nice / Wide and Very adaptable roof profile, If using the 1550mm wide standard outward folded rails  - Narrower RTT can sometimes sit inside the rear anti twist Awning to rack brackets -  without fouling... Meaning excellent results for customers wishing to run the awning independently fitted directly to the rack (So it stays there when the tent is lifted off) If this is of interest - Contact us for more info as only some tents are narrow enough, and usually the tent will require some modifications to sprung steel poles etc to make it all work. 
 
The Tough Touring One Piece  Roof rail design takes away point load issues with traditional gutter mount roof racks, securing immense loads stronger and lower.  The testing run is shown here (Version 1). Its super strong and Super low, the roof tent sitting just 10mm off the roof at the rear of my truck. 
So far  in testing I have noted that the Wind noise is there, but not really any more noticable than the growl of the All Terrain tyres. Quite OK. The 'Hump' on the disco does compress the air coming up the bonnet somewhat. I will add a lightbar at some stage to finish it all off... 
 
Very happy with this rack. Its set up on this truck with a bundutop KING tent - 86Kgs, mattress Included.  the Awning is an Ostrich Junior at 18kgs  Brackets to hold the awning onto the tent are 5kgs and I have 3 pillows, 3 Minus 5 Sleeping bags and sheets in the tent. 1Another 10kgs. 
 
All up the rack is presently carrying 133kgs.  The Car is on 3 Inch lift and 33' Tyres. 
The Newest Design of the rack optioned with 4 x Planks weighs in at 51 Kgs Complete. 1- This coud be reduced to 43 Kts on the rack if Single width planks were used all round, and you could run the rack at 37Kgs with Just three single planks  If desired.
 
Anyway - My Own Disco 2 in pitcures has 163 Kgs on the roof in total -  is a lot of weight. 
Car handles it OK - Body roll is noticable - but then it always was a bit rolly. Not much different to before really. Surprising. I previously ran similar weight on it and it felt worse. But that rack was 80mm higher over all... The Low profile on this one must be working. 
 
If your going to run weights like this on a Disco 1 or 2, be carefull on extreme negative camber surfaces, and reduce your cornering speed.  Better to be safe than experience a roll over. 
The rack handles the weight easy. 

These Racks are being fabricated 5 at a time - and Order to Delivery times can be as long as 3 months... We stress that they are MADE TO ORDER, however to allow customers to buy them we have to list them as 'IN STOCK' on the web page here. Any order made that is not delivered inside a three month time frame is able to be refunded no questions asked.