Here is a profiled shape 1.4*2.1mm silk covered litz wire with single wire 0.08mm and 250 strands, that is customized design. Double silk severed makes the shape looks better, and silk severed layer is not easy to be broken during winding process. The material of silk can be changed, here are main two options Nylon and Dacron. For most European customers, Nylon is the first choice because the water absorption quality is better, however Dacron looks better.