What size is a 6-sheet poster?

I have been asked to produce a shot that is to go on a 6-sheet poster. Can anyon e tell me what this size means, in terms of feet and inches? Thanks.

If I remember correctly, a one-sheet poster is 27" x 41", and a 6- sheet comprises 3 one-sheets across and 2 down, making it 81" x 82". (If I *don't* remember correctly, it would be very close to those measurements!)

Oops, silly typo above where my name should be :)

1200mm x 1800mm

If I remember correctly

Thanks, Ian

Mr. Google, him say: http://www.big-pix.com/size.html