One pair of HL-C-OISD horn loaded 25mm phenolic dome tweeters for sale. They came out of a 1980's pair of Canadian made Sound Dynamics 100S speakers. The front of the precision cast aluminum horn is 137mm in diameter. Extra-large 950g neodymium magnet has a flux density of over 18000 gauss! Can handle over 100w RMS with the included OEM 2250Hz 3rd Order Butterworth crossovers, but can be operated with other networks as well. The depth of the drivers is 61mm's. Used, but in good working condition.