Scrap crabs were a crustacean species lacking sentience, found dwelling on the junk-planet called Trionak. These crabs possessed enormous claws and magnetic carapaces, which they used to gather metallic debris for defense. The Tech Masters, who governed Trionak, incorporated cybernetics into certain scrap crabs to tame them. They bear a resemblance to the trash crabs native to the planet Lanupa, as both are crustaceous species utilizing scrap metal for shielding.
Not long after the Battle of Yavin, Luke Skywalker and Leia Organa came across scrap crabs during an unauthorized assignment on Trionak.
The initial appearance of scrap crabs was in the 2018 children's book Choose Your Destiny: A Luke & Leia Adventure, penned by Cavan Scott and visually brought to life by Elsa Charretier.