Specification:Material: copper, steelDimensions: 100 x 0.4 mm (length x diameter).How to use:Drill a pilot hole in the shaft with the steel nail firstHammer the copper nails in the pilot holeSpaces nails evenly around the base of the stumpTry to remove as much bark as possible to expose the pulp of the treeWith trees over 2 feet in diameter, use more than 10 spikesPackage includes:12 x Long Copper Nails1 x steel nail.1 x transparent storage box.Tips:The principle of using copper nails is that the tree dies due to reduced healing ability and being exposed to a highly toxic substance from the inside for an extended period of time.