In a message dated 2/24/99 10:46:06 PM, debus at cityweb.de wrote: <<In which Hammond organs were they used? In my M-101 the spring is mounted horizontally. >> As for as I know, the vertical/torsional reverb springs were found only in older (1940's - 1050's) Hammond Tone Cabinets (such as PR-40), not in the actual organs. Michael Bacich