The SIJIAWU Tools Professional RJ11 RJ45 Dual Crimping Tool is a professional RJ11 and RJ45 connector crimping tool. This heavy duty crimping tool allows you to make your own RJ11 and RJ45 cables easily and correctly. Multi-function tool cuts, strips and crimps for easy on-the-job, one-tool application. Steel frame for added durability. Crimps primary modular plug strain relief only.