These where made for Bendix King / Relm / Desktop Repeaters, and the desktop base stations. These were never installed, so these are brand new. These can be added to just about anything, If you know how to wire it up. If you look at pictures you can see these installed on the back of the Relm repeaters. Thanks for looking, be sure to check my other items!The item "BK UNIDEN RELM RF POWER AMPLIFIER 25 Watt UHF 25W 450 470 500 Mhz DRU4501B" is in sale since Thursday, May 1, 2014. This item is in the category "Consumer Electronics\Radio Communication\Ham, Amateur Radio\Ham Radio Amplifiers". The seller is "taradios" and is located in Melbourne, Florida. This item can be shipped to United States, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Philippines, Singapore, Switzerland, Norway, Saudi arabia, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Brazil, Chile, Costa rica, Dominican republic, Panama, Trinidad and tobago, Guatemala, El salvador, Honduras, Jamaica, Viet nam, Uruguay, Ecuador, Luxembourg, Paraguay, Russian federation, Aruba, Belize, Dominica, Grenada, Saint kitts and nevis, Turks and caicos islands, Bangladesh, Brunei darussalam, Bolivia, Egypt, French guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Liechtenstein, Monaco, Macao, Martinique, Nicaragua, Peru, Pakistan, Canada.