MADE IN USA. This product is a higher-performance substitute for the aluminum heat sinks that are included with the Survival Laser and DIY Host Assemblies. The copper alloy used in this heat sink has a thermal conductivity of 355 W/m-k which is over 2.1 times that of aluminum, and will allow longer duty cycles without overheating the diode. The SL-CHS1 is sized to fit a 12mm diameter standard diode module and includes a 3-48 set screw (installed) and a 0.050" Allen wrench. Also fits other Aurora C6 18650 hosts.