Hi All, The spirit levels suitable for convertion for elevation readouts are back in stock in British stores (at least) of Lidl. http://www.lidl.co.uk/uk/home.nsf/pages/c.o.20070111.p.Professional_Electric_Spirit_Level.ar11 See http://members.chello.nl/j.swienink1/elevation.html for details on conversion 73 de David GM6BIG