This 4.0 mm Selma® splicing fid is perfect to splice Dyneema®, Vectran® and other braided ropes. The inside diameter is 4.0 mm. This 4.0 mm version is ideal to splice 3 to 4 mm lines. For 5 to 6 mm lines we recommend the 5.5 mm Selma splicing needle (EX13662).