diff --git a/How-to-write-a-browser-exploit-using-BrowserExploitServer.md b/How-to-write-a-browser-exploit-using-BrowserExploitServer.md
index 4dc317c4d1..bd60cbd590 100644
--- a/How-to-write-a-browser-exploit-using-BrowserExploitServer.md
+++ b/How-to-write-a-browser-exploit-using-BrowserExploitServer.md
@@ -81,7 +81,6 @@ The exact values for :ua_name:
 * HttpClients::SAFARI = "Safari"
 * HttpClients::OPERA = "Opera"
 * HttpClients::CHROME = "Chrome"
-* HttpClients::UNKNOWN = "Unknown"
 
 More of these constants can be found here:
 https://github.com/rapid7/metasploit-framework/blob/master/lib/msf/core/constants.rb