TLS stands for Transport Layer Security. EmailOnDeck supports TLS on it's email transactions. This allows emails to be sent in a secure fashion.
You'll see quite a few temporary email generators out there claim they are secure, but they don't even support TLS. It's hard to for us to understand how they can make that claim, but they do. If you're looking to receive email securely with your temporary email, make sure you confirm that their mail server can complete a transactions using TLS. If you're not sure if they can or not, copy and paste the domain of email in question into MXTOOLBOX.com. There you can do a "Test Email Server" lookup or just type: "smtp:DOMAINNAME.com" (without the quotes) and it will let you know if supports SMTP TLS or not. If you find that the domain does not support TLS, understand that your email is most likely not secure while being sent in transit.
At EmailOnDeck.com we are constantly working to provide you with the best temporary email addresses that work. We strive to give you private, secure temp emails that work. We use TLS for our email transactions and allow HTTPS for accessing our sites. We save money by securely deleting our logs every few days.
We hope to continue to provide with the best service for temporary email addresses today and moving forward.
Stay safe out there.