diff --git a/rtio/sed/output_network.py b/rtio/sed/output_network.py
index df76ce2..63632b5 100644
--- a/rtio/sed/output_network.py
+++ b/rtio/sed/output_network.py
@@ -161,7 +161,7 @@ class OutputNetwork(Elaboratable):
                                 m.d.comb += appeared.eq(1)
                         m.d.comb += Assert(appeared)
                 # Otherwise, if there are replacements:
-                # - Channel number are not unique
+                # - Channel numbers are not unique
                 # - Not all outputs are valid
                 # - All channel numbers in the input appear exactly once as a
                 #   valid output