
To protect those details, you can use Lockbin which provides password protection and AES-256 bit encryption to your mails.
How to send password protected mails using Lockbin-
- Click here to go to the Lockbin service.
- Fill in your form with your desired password.
- In that message you can even attach files.
- After this, Click on 'submit' button.
- Now the password protected e-mail will be sent and your reader will only get a link to your encrypted mail.
- When that link is clicked, user will be prompted to enter the password without which it will not open.

This way you can protect your confidential details from hackers.