adjust the size of new popup window

hiiiii all...
I have a code like this
Button1.Attributes.Add("onclick", "javascript:window.open('default2.aspx','height=200,width=400,status=yes,toolbar=no,menubar=no,location=no')")
this is open new window default2.aspx but I want to restirct the size of this new window.. It shows the maximize window size with this code.... what should I do to resize my new open window???

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