Gold Filled square and hard wire.

The gold-filled finish is a treatment widely used in the USA.
This is a 12-carat gold finish applied to a brass base.
The weight of gold corresponds to 1/20 of the total weight of the product, ie approximately 50 to 100 times
more than in a gold-plated product.
Gold-filled jewelery has the appearance of gold jewelery for a much lower cost.
Much more resistant than a gold-plated classic, a gold-filled product will oxidize much less quickly.
If you still want to slow down the oxidation process, you should handle the Gold filled components with gloves
 and avoid contact with perfumes, skin oils and lotions.
You should also keep them in a dry and temperate place.

Bag of about 1.5 meters.