Insulation The experimenter is testing on denim, cotton T-shirt material, wool fabric, thermal underwear, polyester fabric, and a Ziplock bag with no insulator. From research the experimenter learned that wool is a fine soft wavy hair that forms all or part of the protective coat of a sheep. Since ancient times it was harvested to provide clothing and is an important part in textile trade because of its insulation. Woolen fabric is when the woolen system uses short or mixed long and short fiber where no combing is done. It has a rough appearance and is most suitable for blankets, overcoats, and tweeds. Denim which the experimenter is also testing is the m