diff --git a/Appendix-A-Test-Sites.md b/Appendix-A-Test-Sites.md
index e8956be..b735812 100644
--- a/Appendix-A-Test-Sites.md
+++ b/Appendix-A-Test-Sites.md
@@ -53,7 +53,6 @@ These are good sources to grab information on your results in one hit, but **do
 - [DNS Leak](https://www.dnsleaktest.com/) - **h**ttps://www.dnsleaktest.com/
 - [DNS Spoofability](https://www.grc.com/dns/dns.htm) - **h**ttps://www.grc.com/dns/dns.htm
 - [Firefox Storage Test](https://firefox-storage-test.glitch.me/) - **h**ttps://firefox-storage-test.glitch.me/
-- [HSTS [sniffly]](https://zyan.scripts.mit.edu/sniffly/) - **h**ttps://zyan.scripts.mit.edu/sniffly/
 - [HTML5](https://www.youtube.com/html5) - **h**ttps://www.youtube.com/html5
 - [IPv6 Leak](https://ipv6leak.com/) - **h**ttps://ipv6leak.com/
 - [Keyboard Events](https://w3c.github.io/uievents/tools/key-event-viewer.html) - **h**ttps://w3c.github.io/uievents/tools/key-event-viewer.html