diff --git a/api/rtp_parameters.h b/api/rtp_parameters.h
index 342ef0fa48..2ce0b48f8d 100644
--- a/api/rtp_parameters.h
+++ b/api/rtp_parameters.h
@@ -329,9 +329,6 @@ struct RTC_EXPORT RtpExtension {
   bool encrypt = false;
 };
 
-// TODO(deadbeef): This is missing the "encrypt" flag, which is unimplemented.
-typedef RtpExtension RtpHeaderExtensionParameters;
-
 struct RTC_EXPORT RtpFecParameters {
   // If unset, a value is chosen by the implementation.
   // Works just like RtpEncodingParameters::ssrc.
@@ -590,7 +587,7 @@ struct RTC_EXPORT RtpParameters {
 
   std::vector<RtpCodecParameters> codecs;
 
-  std::vector<RtpHeaderExtensionParameters> header_extensions;
+  std::vector<RtpExtension> header_extensions;
 
   std::vector<RtpEncodingParameters> encodings;
 
diff --git a/pc/rtp_parameters_conversion.cc b/pc/rtp_parameters_conversion.cc
index 363fa06006..93f28f1815 100644
--- a/pc/rtp_parameters_conversion.cc
+++ b/pc/rtp_parameters_conversion.cc
@@ -200,29 +200,6 @@ template RTCErrorOr<std::vector<cricket::AudioCodec>> ToCricketCodecs<
 template RTCErrorOr<std::vector<cricket::VideoCodec>> ToCricketCodecs<
     cricket::VideoCodec>(const std::vector<RtpCodecParameters>& codecs);
 
-RTCErrorOr<cricket::RtpHeaderExtensions> ToCricketRtpHeaderExtensions(
-    const std::vector<RtpHeaderExtensionParameters>& extensions) {
-  cricket::RtpHeaderExtensions cricket_extensions;
-  std::set<int> seen_header_extension_ids;
-  for (const RtpHeaderExtensionParameters& extension : extensions) {
-    if (extension.id < RtpHeaderExtensionParameters::kMinId ||
-        extension.id > RtpHeaderExtensionParameters::kMaxId) {
-      char buf[50];
-      rtc::SimpleStringBuilder sb(buf);
-      sb << "Invalid header extension id: " << extension.id;
-      LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_RANGE, sb.str());
-    }
-    if (!seen_header_extension_ids.insert(extension.id).second) {
-      char buf[50];
-      rtc::SimpleStringBuilder sb(buf);
-      sb << "Duplicate header extension id: " << extension.id;
-      LOG_AND_RETURN_ERROR(RTCErrorType::INVALID_PARAMETER, sb.str());
-    }
-    cricket_extensions.push_back(extension);
-  }
-  return std::move(cricket_extensions);
-}
-
 RTCErrorOr<cricket::StreamParamsVec> ToCricketStreamParamsVec(
     const std::vector<RtpEncodingParameters>& encodings) {
   if (encodings.size() > 1u) {
diff --git a/pc/rtp_parameters_conversion.h b/pc/rtp_parameters_conversion.h
index dc24a456fa..35a3725dbe 100644
--- a/pc/rtp_parameters_conversion.h
+++ b/pc/rtp_parameters_conversion.h
@@ -58,10 +58,6 @@ template <typename C>
 RTCErrorOr<std::vector<C>> ToCricketCodecs(
     const std::vector<RtpCodecParameters>& codecs);
 
-// Validates that header extension IDs aren't duplicated.
-RTCErrorOr<cricket::RtpHeaderExtensions> ToCricketRtpHeaderExtensions(
-    const std::vector<RtpHeaderExtensionParameters>& extensions);
-
 // SSRCs are allowed to be ommitted. This may be used for receive parameters
 // where SSRCs are unsignaled.
 RTCErrorOr<cricket::StreamParamsVec> ToCricketStreamParamsVec(
diff --git a/pc/rtp_parameters_conversion_unittest.cc b/pc/rtp_parameters_conversion_unittest.cc
index 44dc0df18e..99d976abcd 100644
--- a/pc/rtp_parameters_conversion_unittest.cc
+++ b/pc/rtp_parameters_conversion_unittest.cc
@@ -301,39 +301,6 @@ TEST(RtpParametersConversionTest, ToCricketCodecsDuplicatePayloadType) {
   EXPECT_TRUE(result.ok());
 }
 
-TEST(RtpParametersConversionTest, ToCricketRtpHeaderExtensions) {
-  std::vector<RtpHeaderExtensionParameters> extensions = {
-      {"http://example.com", 1},
-      {"urn:foo:bar", 14},
-      {"urn:first:two-byte-only:id", 15}};
-  auto result = ToCricketRtpHeaderExtensions(extensions);
-  ASSERT_TRUE(result.ok());
-  ASSERT_EQ(3u, result.value().size());
-  EXPECT_EQ("http://example.com", result.value()[0].uri);
-  EXPECT_EQ(1, result.value()[0].id);
-  EXPECT_EQ("urn:foo:bar", result.value()[1].uri);
-  EXPECT_EQ(14, result.value()[1].id);
-  EXPECT_EQ("urn:first:two-byte-only:id", result.value()[2].uri);
-  EXPECT_EQ(15, result.value()[2].id);
-}
-
-TEST(RtpParametersConversionTest, ToCricketRtpHeaderExtensionsErrors) {
-  // First, IDs outside the range 1-255.
-  std::vector<RtpHeaderExtensionParameters> extensions = {
-      {"http://example.com", 0}};
-  auto result = ToCricketRtpHeaderExtensions(extensions);
-  EXPECT_EQ(RTCErrorType::INVALID_RANGE, result.error().type());
-
-  extensions[0].id = 256;
-  result = ToCricketRtpHeaderExtensions(extensions);
-  EXPECT_EQ(RTCErrorType::INVALID_RANGE, result.error().type());
-
-  // Duplicate IDs.
-  extensions = {{"http://example.com", 1}, {"urn:foo:bar", 1}};
-  result = ToCricketRtpHeaderExtensions(extensions);
-  EXPECT_EQ(RTCErrorType::INVALID_PARAMETER, result.error().type());
-}
-
 TEST(RtpParametersConversionTest, ToCricketStreamParamsVecSimple) {
   std::vector<RtpEncodingParameters> encodings;
   RtpEncodingParameters encoding;