diff --git a/stream.js b/stream.js
index 5b4b59f..7f7764c 100644
--- a/stream.js
+++ b/stream.js
@@ -83,7 +83,7 @@ function WebSocketStream(target, protocols, options) {
   }
 
   // was already open when passed in
-  if (socket.readyState === WS.OPEN) {
+  if (socket.readyState === socket.OPEN) {
     stream = proxy
   } else {
     stream = duplexify.obj()
@@ -103,7 +103,7 @@ function WebSocketStream(target, protocols, options) {
   function socketWriteNode(chunk, enc, next) {
     // avoid errors, this never happens unless
     // destroy() is called
-    if (socket.readyState !== WS.OPEN) {
+    if (socket.readyState !== socket.OPEN) {
       next()
       return
     }
diff --git a/ws-fallback.js b/ws-fallback.js
index 8173b48..aca0c2b 100644
--- a/ws-fallback.js
+++ b/ws-fallback.js
@@ -2,11 +2,11 @@
 var ws = null
 
 if (typeof WebSocket !== 'undefined') {
-  ws = WebSocket
+	ws = WebSocket
 } else if (typeof MozWebSocket !== 'undefined') {
-  ws = MozWebSocket
-} else {
-  ws = window.WebSocket || window.MozWebSocket
+	ws = MozWebSocket
+} else if (typeof window !== 'undefined') {
+	ws = window.WebSocket || window.MozWebSocket
 }
 
 module.exports = ws