Kin'see'ha is a form of structural reinforcing gel created by the Kingdom of Neshaten in late EE 002, and put into service in EE 002-v.
A reinforcing gel, the Kin'see'ha was created to help give Neshaten ships and stations the ability to seal up a hull breach without the use of forcefields or bulkheads. Kin'see'ha is a specialized gel created out several different compounds native to the Neshaten's home system, that can be placed in-between the objects inner and outer hulls. Despite a gel being basically a solid, Kin'see'ha actually remains in a mostly liquid form until it comes into contact with the coldness of space. This allows the gel to be a kind of sealant that plugs a hole, the gel works much like how the one in a Neshaten's armoured body suit does. The gel doesn't have any kind of a protective value against energy, kinetic, or ballistic weaponry and instead is designed purely to deal with a breach in an objects hull, this means that the gel can be shot off of an object but more of it will just take its place.
While the gels chemical make-up allows it to perform this task, it isn't without a drawback; an objects weight is increased when the gel is applied into it, this makes the object 'heavier', but much more durable and capable of withstanding larger degrees of punishment than would be typically possible.
Kin'see'ha is a rather complex gel, comprised of several dozen chemicals and minerals; including depleted Lunabaren crystals which gives it its light-bluish texture.
Kin'see'ha is currently only used on large warships and stations, essentially objects that aren't reliant on speed and/or manoeuvrability but can also be found on specially designed ships such as the Ehe'sii'ne Class Diplomatic vessel.
Think of Kin'see'ha as a foam that exists to seal up a 'wound'. The gel 'oozes' out of the hull breach and turns into a solid upon contact with space.