diff --git a/geomagio/iaga2002/MagWebFactory.py b/geomagio/iaga2002/MagWebFactory.py
index f2bab6c12f4deb79a58ed075e77d3332ff2899d0..11adb2487760f55c0ead0c6efb2a24fd4ac9b140 100644
--- a/geomagio/iaga2002/MagWebFactory.py
+++ b/geomagio/iaga2002/MagWebFactory.py
@@ -13,6 +13,9 @@ MAGWEB_URL_TEMPLATE = 'http://magweb.cr.usgs.gov/data/magnetometer/' + \
 class MagWebFactory(IAGA2002Factory):
     """IAGA2002Factory configured for magweb.cr.usgs.gov"""
 
-    def __init__(self):
+    def __init__(self, observatory=None, channels=None, type=None,
+            interval=None):
         """Create a IAGA2002Factory configured to use magweb.cr.usgs.gov"""
-        IAGA2002Factory.__init__(self, MAGWEB_URL_TEMPLATE)
+        IAGA2002Factory.__init__(self, MAGWEB_URL_TEMPLATE,
+            observatory=observatory, channels=channels, type=type,
+            interval=interval)