diff --git a/bluetooth/1.0/default/h4_protocol.cc b/bluetooth/1.0/default/h4_protocol.cc
index 8c24f76..43abbe4 100644
--- a/bluetooth/1.0/default/h4_protocol.cc
+++ b/bluetooth/1.0/default/h4_protocol.cc
@@ -90,6 +90,7 @@
     hci_packet_type_ = static_cast<HciPacketType>(buffer[0]);
     if (hci_packet_type_ != HCI_PACKET_TYPE_ACL_DATA &&
         hci_packet_type_ != HCI_PACKET_TYPE_SCO_DATA &&
+        hci_packet_type_ != HCI_PACKET_TYPE_ISO_DATA &&
         hci_packet_type_ != HCI_PACKET_TYPE_EVENT) {
       LOG_ALWAYS_FATAL("%s: Unimplemented packet type %d", __func__,
                        static_cast<int>(hci_packet_type_));
diff --git a/bluetooth/1.0/default/hci_internals.h b/bluetooth/1.0/default/hci_internals.h
index 24e944f..6f7ff90 100644
--- a/bluetooth/1.0/default/hci_internals.h
+++ b/bluetooth/1.0/default/hci_internals.h
@@ -44,6 +44,10 @@
 const size_t HCI_EVENT_PREAMBLE_SIZE = 2;
 const size_t HCI_LENGTH_OFFSET_EVT = 1;
 
+// 2 bytes for handle and flags, 2 byte for data length (Volume 4, Part E, 5.4.5)
+const size_t HCI_ISO_PREAMBLE_SIZE = 4;
+const size_t HCI_LENGTH_OFFSET_ISO = 2;
+
 const size_t HCI_PREAMBLE_SIZE_MAX = HCI_ACL_PREAMBLE_SIZE;
 
 // Event codes (Volume 2, Part E, 7.7.14)
diff --git a/bluetooth/1.0/default/hci_packetizer.cc b/bluetooth/1.0/default/hci_packetizer.cc
index 7cb3a11..78ce61d 100644
--- a/bluetooth/1.0/default/hci_packetizer.cc
+++ b/bluetooth/1.0/default/hci_packetizer.cc
@@ -26,17 +26,27 @@
 
 namespace {
 
-const size_t preamble_size_for_type[] = {
-    0, HCI_COMMAND_PREAMBLE_SIZE, HCI_ACL_PREAMBLE_SIZE, HCI_SCO_PREAMBLE_SIZE,
-    HCI_EVENT_PREAMBLE_SIZE};
-const size_t packet_length_offset_for_type[] = {
-    0, HCI_LENGTH_OFFSET_CMD, HCI_LENGTH_OFFSET_ACL, HCI_LENGTH_OFFSET_SCO,
-    HCI_LENGTH_OFFSET_EVT};
+const size_t preamble_size_for_type[] = {0,
+                                         HCI_COMMAND_PREAMBLE_SIZE,
+                                         HCI_ACL_PREAMBLE_SIZE,
+                                         HCI_SCO_PREAMBLE_SIZE,
+                                         HCI_EVENT_PREAMBLE_SIZE,
+                                         HCI_ISO_PREAMBLE_SIZE};
+const size_t packet_length_offset_for_type[] = {0,
+                                                HCI_LENGTH_OFFSET_CMD,
+                                                HCI_LENGTH_OFFSET_ACL,
+                                                HCI_LENGTH_OFFSET_SCO,
+                                                HCI_LENGTH_OFFSET_EVT,
+                                                HCI_LENGTH_OFFSET_ISO};
 
 size_t HciGetPacketLengthForType(HciPacketType type, const uint8_t* preamble) {
   size_t offset = packet_length_offset_for_type[type];
-  if (type != HCI_PACKET_TYPE_ACL_DATA) return preamble[offset];
-  return (((preamble[offset + 1]) << 8) | preamble[offset]);
+  if (type == HCI_PACKET_TYPE_ACL_DATA) {
+    return (((preamble[offset + 1]) << 8) | preamble[offset]);
+  } else if (type == HCI_PACKET_TYPE_ISO_DATA) {
+    return ((((preamble[offset + 1]) & 0x3f) << 8) | preamble[offset]);
+  }
+  return preamble[offset];
 }
 
 }  // namespace
diff --git a/bluetooth/1.0/default/test/h4_protocol_unittest.cc b/bluetooth/1.0/default/test/h4_protocol_unittest.cc
index 283243d..174861c 100644
--- a/bluetooth/1.0/default/test/h4_protocol_unittest.cc
+++ b/bluetooth/1.0/default/test/h4_protocol_unittest.cc
@@ -190,8 +190,10 @@
 
   void WriteAndExpectInboundIsoData(char* payload) {
     // h4 type[1] + handle[2] + size[1]
-    char preamble[4] = {HCI_PACKET_TYPE_ISO_DATA, 20, 17, 0};
-    preamble[3] = strlen(payload) & 0xFF;
+    char preamble[5] = {HCI_PACKET_TYPE_ISO_DATA, 19, 92, 0, 0};
+    int length = strlen(payload);
+    preamble[3] = length & 0xFF;
+    preamble[4] = (length >> 8) & 0x3F;
 
     ALOGD("%s writing", __func__);
     TEMP_FAILURE_RETRY(write(fake_uart_, preamble, sizeof(preamble)));