Well all your doubts can now be set to one side with these indispensible little gizmos from our friends in the US 0f A
http://www.trucknutz.com/
Only in the U S of A could they think of such a vital accessory - probably also keeps a couple of thousand Chinese employed making them too!

And for those that like 'em shiny you can have them in chrome as well! How can carbon have a footprint, it has no feet?
Now driving - RRE Coupe Dynamic Lux Auto with Plus pack, Fuji White, Ebony, SD4 with tow pack
Gone - 2010MY FFRR TDv8 Stornoway and Ivory, Privacy - the pace of a TDv8 RRS, the incomparable grace of a Range Rover
Gone but will be missed- RRS Tdv8 HSE Stornoway Grey with Ebony Leather
Gone (only a little missed) RRS Tdv6 2.7SE Giverny Green/Aspen
Defender 90 County HT in Epsom Green

From the ad it says "Trucknutz are made of solid plastic (the toughest in the industry)." WOW  2007 Freelander 2 HSE TD4 Manual with Premium Pack & Moonroof.
Stornoway Grey with Ebony Black Pleather, Clear Indicators, Body Side Mouldings etc.