diff --git a/setup.cfg b/setup.cfg
index ca56a4c..c32c0f2 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -62,7 +62,7 @@ addopts =
 # wafo/stats/tests
 
 [pep8]
-max-line-length = 100
+max_line_length = 100
 
 [pytest]
 doctest_optionflags = NORMALIZE_WHITESPACE ELLIPSIS