diff --git a/call/rampup_tests.cc b/call/rampup_tests.cc
index 1d584195d2..d0354168cf 100644
--- a/call/rampup_tests.cc
+++ b/call/rampup_tests.cc
@@ -461,7 +461,9 @@ std::string RampUpDownUpTester::GetModifierString() const {
     str += "_";
   }
   str += (rtx_ ? "" : "no");
-  str += "rtx";
+  str += "rtx_";
+  str += (red_ ? "" : "no");
+  str += "red";
   return str;
 }