Back-links are the key to increase the PAGE RANK
Free & Automated backlinks doesn't increase your PR/traffic. Of course it can increase your PR to 2/3, for shorter time. Sure you will be penalized by Google, when you worked with free/automated back-links service providers.
Note: PR is based on the Google pagerank algo & no one knows when they update it. So do not go with FAKE promises. Usually Google updates the PR 2-3 times in a year (Not every month). I heard that some providers give fake redirects for less cost. Be aware of fake redirects.
No one built - free - high quality relevant domain authority back-links for you
Buddy! Its better to built the back-links manually by yourself.