High quality relay box to interface between any radio* and will key any amplifier. RBI-1A Many newer radios can only provide for a small amount of current on the external amplifier keying output. Our box will draw <3 ma from your radio and will key any amplifier. A very handy accessory. Get one BEFORE you damage your radios amplifier keying output! RCA jacks in and out for keying the interface from your radio and output to your amplifier T/R relay control Needs 9-15 VDC at only 40 ma, has 2.1 x 5.5 mm DC jack, universal plug and 5 feet of wire included, center positive Relay rated up to 240 VAC at 5 AMPS! Genuine relay used for switching (not an easy to damage solid state device) See separate eBay listing for RCA-RCA male connector cables Requires GROUND on transmit from your radio to activate Can be used with any radio that has connection for switching to ground for T/R or amplifier control. NOTE: The "competing product" from the big three letter company is $90!!! See our eBay store listings for our complete line of Amplifier Relay Buffer Interfaces. In other listings we have models with 2 radios and a bypass switch, 2 or more amplifiers or other device (like noise reduction unit keying, mute, etc) When connecting your Radio and Amplifier, there may be switching voltage, polarity, and current incompatibility that can cause damage to your radio or amplifier if connected without a switching interface between them. Even if your internal radio switching looks like it might be usable, it is wise to have an extra degree of isolation between your amplifier and radio with our relay buffer interface. 73, Dan W7RF ( Radiodan ) Ham Radio amplifier amateur amatuer radio amplifier relay buffer interface