diff --git a/src/wifi/model/wifi-tx-vector.cc b/src/wifi/model/wifi-tx-vector.cc
index 55725bb4b..c9cdc11ac 100644
--- a/src/wifi/model/wifi-tx-vector.cc
+++ b/src/wifi/model/wifi-tx-vector.cc
@@ -589,6 +589,10 @@ operator<<(std::ostream& os, const WifiTxVector& v)
     {
         os << " Length: " << v.GetLength();
     }
+    if (ns3::IsDlMu(v.GetPreambleType()))
+    {
+        os << " SIG-B mode: " << v.GetSigBMode();
+    }
     if (v.IsMu())
     {
         WifiTxVector::HeMuUserInfoMap userInfoMap = v.GetHeMuUserInfoMap();