The white or blue crystalled dessicant type. I use "Fresh Step"crystals. In a message dated 7/30/2009 8:47:29 PM Pacific Daylight Time, shannonstoney@xxxxxxxxxxxxxxx writes: You mean, any kind of cat litter? Or a special dessicant kind? --shannon Kiron Kid "A photograph that mirrors reality, cannot compare to one that reflects the spirit" **************An Excellent Credit Score is 750. See Yours in Just 2 Easy Steps! (http://pr.atwola.com/promoclk/100126575x1222846709x1201493018/aol?redir=http://www.freecreditreport.com/pm/default.aspx?sc=668072&hmpgID=62&bcd=Jul yExcfooterNO62)