Fiberglass

''High in fiber, high in glass. Everything the body needs.''

Fiberglass is a silicate fiber, glass, used to make insulation. It looks similar to Asbestos.

Obtention
Currently, it is only obtained by acidifying sand in the Ore Acidizer.

Uses
The Soyuz rocket and its Orbital Module.

FEnSU power storage block.

Breeding Reactor core which is used in both the Breeding Reactor and Radiation-Powered Engine.

Insulators. Its insulation crafting recipe is the same as it is for Polymer (two next to each other horizontally).

It is twice as effective as rubber insulation, 16 instead of 8, the same as Asbestos.

Trivia

 * It has a block form, but considering that fiberglass has few uses on its own and that it is somewhat cheap, you might as well just turn it into insulators immediately.
 * Fiberglass bars have been in the game for a while, only recently have they been given use or crafting recipe.
 * Its tooltip reads: "High in fiber, high in glass, everything the body needs".
 * Whether this is a reference or just a witty joke is unconfirmed.