diff --git a/lib/prerender_rails.rb b/lib/prerender_rails.rb
index <HASH>..<HASH> 100644
--- a/lib/prerender_rails.rb
+++ b/lib/prerender_rails.rb
@@ -2,7 +2,7 @@ module Rack
   class Prerender
     require 'net/http'
 
-    DISALLOW_PHANTOMJS_HEADERS = %w(
+    DISALLOWED_PHANTOMJS_HEADERS = %w(
       cache-control
       content-length
       content-type
@@ -154,7 +154,7 @@ module Rack
 
       # Pass through only applicable 
       prerendered_response.each do |name, val|
-        next if DISALLOW_PHANTOMJS_HEADERS.include? name
+        next if DISALLOWED_PHANTOMJS_HEADERS.include? name
         Rails.logger.debug "Prerender response header: #{name} #{val}"
         response[name] = val
       end
Better naming for phantomjs filtered headers constant.