I searched and found a boat load of Clays info..
http://www.brianenos.com/forums/index.php?showtopic=184169&hl=%2Bclays#entry2035592
http://www.brianenos.com/forums/index.php?showtopic=131870&hl=%2Bclays#entry1485135
http://www.brianenos.com/forums/index.php?showtopic=130794&hl=%2Bclays#entry1473637
http://www.brianenos.com/forums/index.php?showtopic=105461&page=2&hl=%2Bclays#entry1383300
http://www.brianenos.com/forums/index.php?showtopic=105673&hl=%2Bclays#entry1202111
plus a few dozen more threads...