This is for a new, replacement 3/4 inch Dome Highrange Driver (Tweeter) for the AR-LST. This is the last that we have. The tweeter is no longer available. This is a 3/4 inch fabric dome tweeter. The hole line up is in the same location as the originals, Inherrently, the frequency response dips down a bit into the midrange. To duplicate the response of the LST tweeter, we have added a crossover capacitor to the rear. Tested and installed for several years in several pair of AR-LST speakers with great results. We expect this to outlast any of the original tweeters. If you are going to have a driver failure, the tweeter is the most likely candidate. Due to the complex crossover network of the LST, it is not easy to locate a suitable substitute as the one we offer for the AR-3a. Additionally, we are finding that many if not most LST tweeters are suffering from low output volume similar to the AR-3a tweeters. This tweeter significantly increases the volume of the tweeter array. We suggest the center of the cabinet if possible. This tweeter has push on rear terminals but in different locations than the originals. You will most likely need to notch the mounting rim to accommodate the terminals. Drill in the new locations works well. Later production utilized this rear terminal mount. If you have the front wired type, we suggest you drill a 3/16 in. Hole next to the original front mounted terminals; bring the wires up to the front panel terminals and solder. Fill any remaining void with our cabinet sealer. The rear gasket is included. Please browse our entire store, VINTAGE AR PART AND SERVICE. We have over 200 items for the AR fan and are continuing to add new items. If you would like to be advised of new items and our occasional sales, please sign up for our Newsletter. The item “ACOUSTIC RESEARCH REPLACEMENT FOR THE AR-LST TWEETER” is in sale since Tuesday, March 31, 2020. This item is in the category “Consumer Electronics\Vintage Electronics\Vintage Audio & Video\Vintage Speakers”. The seller is “vintage-ar” and is located in Albany, New York. This item can be shipped worldwide.