diff --git a/oceans/filters.py b/oceans/filters.py
index 79b952f..7e857e6 100644
--- a/oceans/filters.py
+++ b/oceans/filters.py
@@ -621,8 +621,7 @@ def pl33tn(x, dt=1.0, T=33.0, mode="valid", t=None):
     if isinstance(x, xr.DataArray):
         dt = (x.cf["T"][1] - x.cf["T"][0]) / np.timedelta64(
             360_000_0000_000,
-        )  # This is a bit more readable.
-        # dt = (x.cf["T"][1] - x.cf["T"][0]) * 1e-9 / 3600
+        )
     elif isinstance(x, pd.Series):
         dt = (x.index[1] - x.index[0]) / pd.Timedelta("1H")