I can't remember where I got these 18" antennas actually or what the DB gain is but I had them in my closet from a WiFi project a couple of years back. I thought - hey with my new DBS MOD I also gained a standard SMA connector to try other antennas. So I gave these a try. Wouldn't you know it - to about a mile out they perform actually BETTER than the DBS MOD antenna since I don't have to point the controller almost straight up and I can adjust each antenna independently. Now after about a mile or around 6K feet my reception drops like a cliff to quickly disconnected just like the DBS MOD antenna. Hmm... maybe that has to do with the antenna on the P3 or even the software not being optimized for >1 mile range? DOM .