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

https://highstylife.com/how-do-i-tell-if-a-backlink-is-relevant-or-just-high-da-fluff/

Tiered link building uses two levels of backlinks to boost your site’s authority safely. Tier 1 links point directly to your site and are high quality. Tier 2 links support Tier 1 by linking to those backlinks, helping increase their value