Hi Mike, The pictures are attached. The circle traced by the outer tip of the blades is 18 &1/2 inches. However if you measure across the fan thru the centreline of the unit you only get 18 inches since the individual blade tips never line up along a centreline. I believe that the 18 & 1/2 inch and 18 inch designations are for the same fan unit. The pictures show the fan that was on my 2nd H when I purchased it and the blades are aluminium. I read somewhere that the blades on a H should be steel and not aluminium. I have installed fans with steel blades on both of my cars. Doug Warrener [Non-text portions of this message have been removed] ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to http://autos.groups.yahoo.com/group/Chrysler300/join and select the "Leave Group" button For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylangYahoo Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: Chrysler300-digest@xxxxxxxxxxxxxxx Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo Groups is subject to: http://info.yahoo.com/legal/us/yahoo/utos/terms/