This Gunshot Residue Kit is a two part Forensic Chemistry test to determine whether a surface has been exposed to a discharged firearm. A rapid colour change takes place to verify the presence of nitrates and lead.Kit contains instructions and enough materials for 30 tests.Kit contents include:1 x 5ml diphenylamine sulfuric acid solution1 x 0.025g sodium rhodizonate1 x 5ml lead nitrate 0.05M aqueous solution20 alcohol swabsIdeal for KS3 and KS4* Please Note: The tests included with this kit are suitable for use in schools. They are not suitable for diagnostics or commercial use*