Flexsteel

Karen Lowachee for Flexsteel Scrapjack, and Ceekayell for the War Droids.

Flexsteel is the combined material used to build ships, stations, moon bases, satellites — it is the backbone of the Cores. The gathering and transformation of various metallic elements found throughout the Cores drives the industry of power not only in these Cores, but throughout all twelve.
This material is where the derogatory term of 'Flexie' when referring to a War Droid, since their chassis is primarily composed of this alloy.