The best splicers offer core alignment, fast splice times, durable designs, and smart features like cloud syncing and automated calibration. The M5 Fiber Optic Fusion Splicer is an intelligent, fully automatic fusion tool engineered for fast, accurate, and reliable splicing of SMF, MMF, DSF, and NZDSF fibers. With a 6-motor core alignment system, the M5 ensures low splice loss, higher efficiency, and precise positioning compared to. Fusion splicers are essential for creating low-loss, high-performance fiber optic connections in telecom, FTTH, and data center applications. Top-rated models. When it comes to optical fiber fusion splicers, no other company in the world can match Sumitomo Electric Lightwave for innovation, speed, and performance.