With the motif of umpire pants, a large pocket is placed from the waist to the hips. Umps Pants are made of a dry cotton blend from the USA and Australia, using yarns spun in a way that creates neps by adjusting the machine when carding the raw cotton (a process to remove impurities and align the fibers in a certain direction). This is a very technical process, and it is difficult to get the neps to be strong or weak. On the other hand, it has a natural and rustic look. Since nep yarn is a weak yarn that breaks more easily than usual, delicate control is necessary when weaving. Therefore, Jackman uses an old-fashioned "rapier loom," which is capable of weaving with strength on weak yarns such as silk.
