15 copper nails, 1 cobalt drill nail, etc. A set of tools for removing tree stumps, which can meet daily use and replacement needs. The size of the hardware nails for trees and stainless steel nails is 3.14 inches x 3 mm, and the size of the drill nails is 2.3 inches x 3 mm. It helps to remove stumps and roots by releasing excessive copper ions to damage tree growth. These hardware copper nail stump killer sets are mainly made of pure copper and stainless steel, which are durable, rust-proof and corrosion-resistant. The copper nail stump killer is made of 99% pure copper, which is thicker than other products and has a long service life; the drill bit is made of cobalt-containing high-speed steel, which is resistant to high temperature, wear and deformation. Copper is a soft material, drill holes on the roots, then hammer the copper nails into the holes, and finally evenly place the nails around the bottom of the stump. The stump killer can be taken out and reused after use. Trees with a diameter greater than 2 feet require 10 or more copper nails. This versatile copper nail stake killer kit is not only great for killing unwanted trees, stumps and roots, but can also be used as a helpful tool for different DIY projects. The principle behind using copper nails is that trees die from reduced healing ability and long-term exposure to excessive copper ions inside. Colour:As Shown Material:copper Size:Copper nails for killing trees:about 3.14 inches x 3. mm, Drill nails:about 2.3 inches x 3 mm. Package Contents: 1set * stump remover Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.