MasterLine is the name given to a range of TÜV tested safety guards. These are usually mounted behind the rear seats, held against the back of the ‘C’ pillar without the need to e.g. drill metal and fix attachments to the car. The pictures show a typical fixing system with the guard held in place with a thin steel plate hooked around the rear seat securing pins.
The purpose of MasterLine is to protect the passengers from items in the boot being flung forward in the event of an accident. This is a serious issue - a frozen chicken travelling forwards at 40mph may well be lethal. There are important guidelines and legislation covering for example front and rear crumple zones, seat belts, child seat fixings, but very little formal attention has been paid to the dangers lurking in the car boot.
Every MasterLine safety guard is tested separately at TÜV in the relevant car. TÜV don’t actually crash every car but whack a ram into the back of the MasterLine with a force equivalent to a 90kph collision.
MasterLine allows you to fill the car boot to full height, making better use of the boot space. It also makes a brilliant dog guard.
With most cars the boot roller can be left in place, and it doesn't usually take more than a couple of minutes to fit or remove a MasterLine.
In summary, this is a product which may look expensive at first glance but it will certainly provide real peace of mind and, the more you think about it, may well assume the status of "essential accessory".