Manufacturer Part Number: RPH20 Affordable durable horns for demanding sound reinforcement applications. Key Features: Large horn mouth extends response to lowest possible frequency Weatherproof aluminum construction Stainless steel hardware for long service life Suitable for indoor or outdoor installations Standard 1-3/8 -18 threaded throat Dayton Audio RPH20 20 Round PA Horn Pair Affordable durable horns for demanding sound reinforcement applications. The re-entrant style horn flare design provides an expansion path that is longer than conventional straight horns; this ensures that the lowest possible frequency response can be achieved. The Dayton Audio RPH-20 PA horns are formed from lightweight aluminum and painted with a durable polyester finish so you know that they will survive years of exposure to sun and rain. Great for indoor or outdoor applications sturdy mounting yoke for precise alignment included. Standard 1-3/8 -18 threaded throat; 20 mouth diameter 13 depth. Now sold in Pairs Product Details BrandDayton AudioModelRPH20Part Number300-196UPC844632008030Unit of MeasureEachWeight7.25