I made many prototypes and tests with this first batch, so the number of brushes available in J1 was quite low. The two-band hair is characterized by tips that are very pleasantly soft even without a gel effect. 

I've tried different tying techniques and variations of density, shape, and loft, and I ultimately think a tightly packed fan knot with a relatively high loft is where this hair can shine. All J1 knots are packed very densely, have a diameter of 27 mm and a free loft of 53.5 mm.