diff --git a/ws/message.go b/ws/message.go
index 8ca95ea..e577eb7 100644
--- a/ws/message.go
+++ b/ws/message.go
@@ -153,6 +153,11 @@ func (m Message) Send(socket net.Conn) error {
 
 	header := make([]byte, 0, maximumHeaderSize)
 
+	// fix size
+	if uint(len(m.Data)) <= m.Size {
+		m.Size = uint( len(m.Data) )
+	}
+
 	/* (1) Byte 0 : FIN + opcode */
 	header = append(header, 0x80 | byte(TEXT) )
 
@@ -182,7 +187,7 @@ func (m Message) Send(socket net.Conn) error {
 	/* (3) Build write buffer */
 	writeBuf := make([]byte, 0, len(header) + int(m.Size))
 	writeBuf = append(writeBuf, header...)
-	writeBuf = append(writeBuf, m.Data...)
+	writeBuf = append(writeBuf, m.Data[0:m.Size]...)
 
 	/* (4) Send over socket */
 	_, err := socket.Write(writeBuf)