Eastern Leaf copper wire is 100% made in the USA at our facility and kiln fired at high temperatures for optimal annealing. The result is a soft flexible wire when applying to your tree's branches. Work hardening your copper bonsai wire once it is on the branch results in strong holding power on the branch. Copper bonsai wire is great for your best trees due to their ability to hold branches without requiring a higher gauge. The copper bonsai wire will also patina and blend with the branch color over time.