diff --git a/aosstower/level_a0/nc.py b/aosstower/level_a0/nc.py
index 4634288854ddc80de1d393bde0d145ae3a33d48b..c412df5aaec52a0063682bdcada3e72d35cd4096 100644
--- a/aosstower/level_a0/nc.py
+++ b/aosstower/level_a0/nc.py
@@ -188,7 +188,8 @@ def createGiantNetCDF(start, end, inputFiles, outputName, zlib, chunkSize):
 
     frame = getData(inputFiles)
 
-    frame = frame[start.strftime('%Y-%m-%d %H:%M:%S'): end.strftime('%Y-%m-%d %H:%M:%S')]
+    if(start and end):
+        frame = frame[start.strftime('%Y-%m-%d %H:%M:%S'): end.strftime('%Y-%m-%d %H:%M:%S')]
 
     firstStamp = dt.strptime(str(list(frame.index)[0]), '%Y-%m-%d %H:%M:%S')
 
@@ -204,6 +205,18 @@ def createGiantNetCDF(start, end, inputFiles, outputName, zlib, chunkSize):
     ncFile = writeVars(ncFile, frame)
 
     ncFile.close()
+
+def createMultiple(filenames, outputFilenames, zlib, chunkSize):
+    if(outputFilenames and len(filenames) != len(outputFilenames)):
+        print('USAGE: number of output filenames must equal number of input filenames when start and end times are not specified')
+        exit(0)
+    
+    for idx, filename in enumerate(filenames):
+         if(outputFilenames):
+             createGiantNetCDF(None, None, [filename], outputFilenames[idx], zlib, chunkSize)
+
+         else:
+             createGiantNetCDF(None, None, [filename], None, zlib, chunkSize)
     
 #The purpose of this method is to take a string in the format
 # YYYY-mm-ddTHH:MM:SS and convert that to a datetime object
@@ -235,7 +248,7 @@ def main():
     parser.add_argument("input_files", nargs="+",
                          help="aoss_tower level_00 paths")
 
-    parser.add_argument('-o', '--output', help="filename pattern or filename. " +
+    parser.add_argument('-o', '--output', nargs="+", help="filename pattern or filename. " +
     "Should be along the lines of <filepath>/aoss_tower.YYYY-MM-DD.nc")
     args = parser.parse_args()
 
@@ -247,6 +260,6 @@ def main():
         createGiantNetCDF(args.start_time, args.end_time, args.input_files, args.output, args.zlib, args.chunk_size)
 
     else:
-        createNetCDF(args.input_files, args.ouput)
+        createMultiple(args.input_files, args.output, args.zlib, args.chunk_size)
 if __name__ == "__main__":
     main()