diff --git a/multiaddr_test.go b/multiaddr_test.go
index 5c3d256..3028605 100644
--- a/multiaddr_test.go
+++ b/multiaddr_test.go
@@ -157,9 +157,9 @@ func TestStringToBytes(t *testing.T) {
 		}
 	}
 
-	testString("/ip4/127.0.0.1/udp/1234", "047f0000011104d2")
+	testString("/ip4/127.0.0.1/udp/1234", "047f000001910204d2")
 	testString("/ip4/127.0.0.1/tcp/4321", "047f0000010610e1")
-	testString("/ip4/127.0.0.1/udp/1234/ip4/127.0.0.1/tcp/4321", "047f0000011104d2047f0000010610e1")
+	testString("/ip4/127.0.0.1/udp/1234/ip4/127.0.0.1/tcp/4321", "047f000001910204d2047f0000010610e1")
 }
 
 func TestBytesToString(t *testing.T) {
@@ -184,9 +184,9 @@ func TestBytesToString(t *testing.T) {
 		}
 	}
 
-	testString("/ip4/127.0.0.1/udp/1234", "047f0000011104d2")
+	testString("/ip4/127.0.0.1/udp/1234", "047f000001910204d2")
 	testString("/ip4/127.0.0.1/tcp/4321", "047f0000010610e1")
-	testString("/ip4/127.0.0.1/udp/1234/ip4/127.0.0.1/tcp/4321", "047f0000011104d2047f0000010610e1")
+	testString("/ip4/127.0.0.1/udp/1234/ip4/127.0.0.1/tcp/4321", "047f000001910204d2047f0000010610e1")
 	testString("/onion/aaimaq4ygg2iegci:80", "bc030010c0439831b48218480050")
 }
 
diff --git a/protocols.go b/protocols.go
index 75e1349..9f78f98 100644
--- a/protocols.go
+++ b/protocols.go
@@ -27,7 +27,7 @@ const (
 	P_UDP   = 0x0111
 	P_DCCP  = 0x0021
 	P_IP6   = 0x0029
-	P_QUIC  = 0x0051
+	P_QUIC  = 0x01CC
 	P_SCTP  = 0x0084
 	P_UDT   = 0x012D
 	P_UTP   = 0x012E