Those look exactly like the ones I have, cheaper too by about $20, IIRC. I got mine at BB some years back when they were on sale, then they disappeared from the store never to return. Radio Shack had a similar product, might still offer it, but it was a bit more expensive. (What was the little antenna for? The instructions said something about "future technology" but then I never learned anything more about that feature.)
I had 2 pairs of these and used them to send SD signals from my 2 Dish receivers to 2 additional locations. The signals are quite directional, but my setup was in a bit of a "crossfire" configuration so each leapfrog receiver could receive both transmitted signals fairly reliably. That way the 2 TVs in remote locations could choose either of 2 different programs, whatever was being watched on the 2 Dish receivers, simply by the user changing the frequency switch on the leapfrog receiver at that location. I used IR repeaters so I could control the Dish receivers in both remote locations but that was not quite as reliable.
Yeah - I'm waiting for an HD version in that price range as well, but it looks like that may be quite a while...!
(Sorry to Shanghai the thread...!)