Tiered link building uses two levels of backlinks to boost your site’s...

https://jaspersexpertinsight.iamarrows.com/do-i-really-need-tier-3-links-or-should-i-stop-at-tier-2

Tiered link building uses two levels of backlinks to boost your site’s authority. Tier 1 links point directly to your site, while Tier 2 links support those Tier 1 backlinks