Troges flexible sound attenuators are telephony sound absorbers and consist of two flexible aluminium tubes with an insulation layer between. The inner tube is machine-perforated. The end caps consist of necks for the pipe connection, corresponding to the standard diameter of spiral-seam pipes and flexible aluminium hoses. Telephony sound absorbers can be supplied in insulation thicknesses of 25 mm or 50 mm and can be fitted quickly and easily in any desired position.