Suitable for all kinds of equipment designed according to 19 machine frame standard, and can be easily disposed for particular needs. The fusing distribution board of the unit box is double side structure, integrating the fusing and distribution into one unity, suitable for fibbon or non-ribbon optical fiber cable. Every board can be clamped with 12FC or SC adaptors which bevel the face side with 30 degrees.That not only ensures the curvature radiius of fiber, but also prevents the eyes from highlight. There is a cover-plate on the tray after fusion.