Premium Microfiber Unpadded Fitted Sheet for King Bed From microfiber Smooth and warm. It uses fibers that are even finer than microfiber, giving it a softer texture and smoother feel against the skin. It also has a higher fiber count, so it feels even warmer. We compared it with conventional microfiber and the difference is immediately obvious! By tightly packing it with fibers that are even finer than microfiber and making the pile longer, it feels much smoother against the skin and is fluffy and warmer than conventional microfibers.