Do NOT buy that for a UHF radio. You will most likely damage the finals. That is far too much spacing in frequency to even try to play with. Essentially you will just turn all of your forward power into reflected power back into the radio.
Edit: I know they say it will do up to 512 Mhz, but I am assuming they are talking about receive, because if it isn't then you essentially are just strapping a dummy load to your radio and hoping that by sheer power you can have someone hear you.