This tool greatly simplifies the insertion of cables into split sleeves. It works very well and is designed for 20 mm diameter sleeves—scale as needed. Recommended materials: PLA, ABS. No support is required. The design is sturdy and safe, with no sharp edges or dangerous parts. The symmetric version closes the sleeve around the cable at the same time on both sides, while the left-hand version is especially suited for winged sleeves, always closing the left wing first. To obtain the right-hand version, use the mirror function.