diff --git a/proxy/kcp/kcp.go b/proxy/kcp/kcp.go
index 1123f74..54b354e 100644
--- a/proxy/kcp/kcp.go
+++ b/proxy/kcp/kcp.go
@@ -133,7 +133,7 @@ func NewKCPServer(s string, dialer proxy.Dialer) (proxy.Server, error) {
 
 	// prepare transport listener
 	// TODO: check here
-	if len(transport) < 2 {
+	if len(transport) != 2 {
 		return nil, errors.New("[kcp] malformd listener:" + s)
 	}
 
diff --git a/proxy/tls/tls.go b/proxy/tls/tls.go
index e795e27..8b8b298 100644
--- a/proxy/tls/tls.go
+++ b/proxy/tls/tls.go
@@ -92,7 +92,7 @@ func NewTLSServer(s string, dialer proxy.Dialer) (proxy.Server, error) {
 
 	// prepare transport listener
 	// TODO: check here
-	if len(transport) < 2 {
+	if len(transport) != 2 {
 		return nil, errors.New("[tls] malformd listener:" + s)
 	}
 
diff --git a/proxy/unix/unix.go b/proxy/unix/unix.go
index 0a43e62..c220841 100644
--- a/proxy/unix/unix.go
+++ b/proxy/unix/unix.go
@@ -51,7 +51,7 @@ func NewUnixServer(s string, dialer proxy.Dialer) (proxy.Server, error) {
 
 	// prepare transport listener
 	// TODO: check here
-	if len(transport) < 2 {
+	if len(transport) != 2 {
 		return nil, errors.New("[unix] malformd listener:" + s)
 	}