diff --git a/pyemu/mat/mat_handler.py b/pyemu/mat/mat_handler.py
index 1786e910..e0742a04 100644
--- a/pyemu/mat/mat_handler.py
+++ b/pyemu/mat/mat_handler.py
@@ -37,7 +37,7 @@ def save_coo(x, row_names, col_names, filename, chunk=None):
     header = np.array((x.shape[1], x.shape[0], x.nnz), dtype=Matrix.binary_header_dt)
     header.tofile(f)
 
-    data = np.core.records.fromarrays([x.row, x.col, x.data], dtype=Matrix.coo_rec_dt)
+    data = np.rec.fromarrays([x.row, x.col, x.data], dtype=Matrix.coo_rec_dt)
     data.tofile(f)
 
     for name in col_names:
@@ -1897,7 +1897,7 @@ def to_coo(self, filename, droptol=None, chunk=None):
 
         if chunk is None:
             flat = self.x[row_idxs, col_idxs].flatten()
-            data = np.core.records.fromarrays(
+            data = np.rec.fromarrays(
                 [row_idxs, col_idxs, flat], dtype=self.coo_rec_dt
             )
             data.tofile(f)
@@ -1908,7 +1908,7 @@ def to_coo(self, filename, droptol=None, chunk=None):
                 # print(row_idxs[start],row_idxs[end])
                 # print("chunk",start,end)
                 flat = self.x[row_idxs[start:end], col_idxs[start:end]].flatten()
-                data = np.core.records.fromarrays(
+                data = np.rec.fromarrays(
                     [row_idxs[start:end], col_idxs[start:end], flat],
                     dtype=self.coo_rec_dt,
                 )
@@ -2052,7 +2052,7 @@ def to_binary(self, filename, droptol=None, chunk=None):
 
         if chunk is None:
             flat = self.x[row_idxs, col_idxs].flatten()
-            data = np.core.records.fromarrays([icount, flat], dtype=self.binary_rec_dt)
+            data = np.rec.fromarrays([icount, flat], dtype=self.binary_rec_dt)
             # write
             data.tofile(f)
         else:
@@ -2060,7 +2060,7 @@ def to_binary(self, filename, droptol=None, chunk=None):
             while True:
                 # print(row_idxs[start],row_idxs[end])
                 flat = self.x[row_idxs[start:end], col_idxs[start:end]].flatten()
-                data = np.core.records.fromarrays(
+                data = np.rec.fromarrays(
                     [icount[start:end], flat], dtype=self.binary_rec_dt
                 )
                 data.tofile(f)