Profile: Echo, Inc. specializes in the manufacturing of thermometers. We are the manufacturer of glass thermometer tubes and carded tubes. Echo tubes are made within the standard commercial tolerance of two degrees fahrenheit. Our tubes are filled with a non-toxic fluid that absolutely will not fade. The filling is available in two colors red and blue. Echo thermometer tubes are so constructed that even when subjected to prolonged periods of extremely high temperatures, the fluid will not adhere in the top of the tube. We manufacture standard tubes to provide temperature readings to meet normal top registration up to 130 degrees fahrenheit, which is considered adequate for normal indoor/outdoor applications and high temperatures up to 240 degrees fahrenheit. Our standard tubes and carded tube sizes are 2", 2 1/2", 3", 4", 5", 6", 6 1/2", 7", 8" and 12". All tubes are marked at 70 degrees with a black positioning line.