Shure will try to charge you four times what the cost should be, because they refuse to tell you the impedance rating of their gear, to force you to buy their own, badly over priced cables. Shure PSM 300 runs at 50 ohms impedance throughout, this fits and works perfectly, and is a quarter the price. There is also a thomann antenna connection panel that is compatible at 50 ohms too, there are also 50 ohm bcc connectors for sale here?, so you can connect many shorter cables, into one big long cable. Works great.