... keypad RS-485 interface for networking.UltrasonicTS-1:small size Tran.(magnetic) for pipe size: DN15~100mm,liquid temperature ≤110°COptions ... : TM-1: medium size Tran. (magnetic) for pipe size: DN50~1000mm, liquid temperature≤110°C ... , TL-1:Large size tran. (magnetic) for pipe size: DN50~1000mm; liquid temperature ≤110° ...