Practical crimping tool for connectors on telephone handsets RJ10, telephones, fax machines, and modems RJ11, RJ12, with an additional cable cutter and stripper for 6 mm and 12 mm for unshielded flat cables. Particularly precise results are achieved through parallel crimping. The stripper neatly strips the cable to 6 mm when inserted at an angle and to 12 mm when inserted straight. It includes a longitudinal cutter for flat cables, such as telephone cables. The forced lock prevents the tool from opening too early, allowing it to open only after the handles have been fully compressed. If the tool gets stuck during the crimping process, for example due to trapped foreign objects, it can be reopened using the integrated emergency release. The lever mechanism allows for energy-saving opening and closing of the crimping tool, preventing hand fatigue.