diff --git a/src/filesystem/implementation.js b/src/filesystem/implementation.js
index 09fe361..2c6cc69 100644
--- a/src/filesystem/implementation.js
+++ b/src/filesystem/implementation.js
@@ -1629,7 +1629,7 @@ function open(fs, context, path, flags, mode, callback) {
   */
   if (arguments.length == 5){
     callback = arguments[arguments.length - 1];
-    mode = 0o666;
+    mode = 0o644;
   }
   else {
     //need to test this validateAndMakeMode
@@ -1928,8 +1928,8 @@ function validateAndMaskMode(value, def, callback) {
     callback = def;
     def = undefined;
   }
-
   if (isUint32(value)) {
+    let newMode = value & FULL_READ_WRITE_EXEC_PERMISSIONS;
     return value & FULL_READ_WRITE_EXEC_PERMISSIONS;
   }
 
diff --git a/tests/spec/fs.open.spec.js b/tests/spec/fs.open.spec.js
index b995755..474fd23 100644
--- a/tests/spec/fs.open.spec.js
+++ b/tests/spec/fs.open.spec.js
@@ -106,6 +106,24 @@ describe('fs.open', function() {
     });
   });
 
+
+  it('should create a new file, when flagged for write, and set the mode to the passed value', function(done) {
+
+    var fs = util.fs();
+    fs.open('/myfile', 'w', 0o777, function(error) {
+      if(error) throw error;
+
+      fs.stat('/myfile', function(error, result) {
+        expect(error).not.to.exist;
+        expect(result).to.exist;
+        expect(result.mode).to.exist;
+        expect(result.mode & 0o777).to.equal(0o777);
+        done();
+      });
+    });
+  });
+
+  
   /**
    * This test is currently correct per our code, but incorrect according to the spec.
    * When we fix https://github.com/filerjs/filer/issues/314 we'll have to update this.