Xtralis 4mm Microbore Tube, UL listed and labeled for plenum use, meets NFPA 72 sampling tube labeling requirements: “Aspirated Sampling Tubing for Fire Detection Use – Do not Disturb or Paint,” each roll is individually serialized for ease of identification and have footage markers every 3 feet for ease of measurement. Xtralis microbore tubing has been tested for smoke transmission, do not substitute. Enter quantity in in linear feet required. Sold in 500 ft roll, Price shown is per roll.