What makes the MagnaValve green?

Author:  Dave Eggleston, Engineer, Electronics Inc.
Source:  The Shot Peener magazine, Vol 18 / Issue 2, Spring 2004
Doc ID:  2004027
Year of Publication:  2004
Abstract:  
The MagnaValve is an environmentally responsible product-it conserves energy and media. Invented by Electronics Inc. in 1983, the MagnaValve is a magnetic valve that will regulate the flow of steel shot used in abrasive blast cleaning or shot peening applications. The valve has a permanent magnet that stops the shot flow and also an electro-magnet that allows the shot to flow by canceling the permanent magnet. There are no moving parts in the MagnaValve so there is nothing to break or wear out.