Syncro 4&4 Discussion and Q&A last answered over 2 years ago.
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the green ones that Doug made up for us from 'surplus-preloved' varied in size from Standard down to coffee cup size and having a bunch of smaller ones is generally useful for us, levelling vans on camping, infilling ruts, supporting and bridging with longer boards, high lift jack plate, axle stand/bottle jack plate, my big ones are only just over 1.1m, I wanted them short enough to fit in the locker box on the back when I had that
I've used the smaller 2/3 size ones more than the big ones - they are only 30mm so big ones can't take the load without the smaller ones to support them when bridging too
I recently found out what this stuff is actually for. I screeded a floor in a sub station and under the waffle boards is a trench a couple of meters deep for all the cables to run.
did a bit of searching and found a uk company http://www.hrfibreglass.co.uk/" onclick="window.open(this.href);return false;
not too sure but i think they have it