There are times when just a comment isn't enough, but you need images to describe it. In these instances, you can easily attach a file to a comment. Useful also when you need to send files like the latest logo or a photo. 

You'll find Attach File link below your comment. Both reviewers and team members can upload attachments.

You can attach files in PNG, PSD, PDF, JPG and ZIP format with max file size up to 100MB.