diff --git a/quic/core/congestion_control/bbr_sender.cc b/quic/core/congestion_control/bbr_sender.cc
index aa81d5a..c455751 100644
--- a/quic/core/congestion_control/bbr_sender.cc
+++ b/quic/core/congestion_control/bbr_sender.cc
@@ -109,7 +109,7 @@
       pacing_gain_(1),
       congestion_window_gain_(1),
       congestion_window_gain_constant_(
-          static_cast<float>(FLAGS_quic_bbr_cwnd_gain)),
+          static_cast<float>(GetQuicFlag(FLAGS_quic_bbr_cwnd_gain))),
       num_startup_rtts_(kRoundTripsWithoutGrowthBeforeExitingStartup),
       exit_startup_on_loss_(false),
       cycle_current_offset_(0),
diff --git a/quic/core/congestion_control/bbr_sender_test.cc b/quic/core/congestion_control/bbr_sender_test.cc
index be4f291..5a7ee40 100644
--- a/quic/core/congestion_control/bbr_sender_test.cc
+++ b/quic/core/congestion_control/bbr_sender_test.cc
@@ -374,7 +374,7 @@
 // Test a simple long data transfer with 2 rtts of aggregation.
 TEST_F(BbrSenderTest, SimpleTransferAckDecimation) {
   // Decrease the CWND gain so extra CWND is required with stretch acks.
-  FLAGS_quic_bbr_cwnd_gain = 1.0;
+  SetQuicFlag(FLAGS_quic_bbr_cwnd_gain, 1.0);
   sender_ = new BbrSender(
       bbr_sender_.connection()->clock()->Now(), rtt_stats_,
       QuicSentPacketManagerPeer::GetUnackedPacketMap(