2pcs 433 Mhz SMA Gmrs Antenna High Frequency 3dbi with SMA Male Connector - 433Mhz GSM GPRS Omni Antenna for Alarm System

Great for flipper zero 433mhz signals

I opened this just long enough to test on an analyzer, and it is completely unresonant on the 400-480MHz bands with SWRs >20 across the band. Weirdly only resonant with 1.3 SWR at 1.034 GHz, but almost nowhere else. Definitely worse than any stock antenna your devices came with, and definitely not useable at 433MHz as advertised. Both antennas tested the same. Didn’t deconstruct, but wouldn’t be surprised to find just a rusted nail inside the plastic — although that might actually be more resonant than this antenna.

I got these for better range out of my 466 MHz transmitter, but the range is not as good as a simple wire. I am told these need a ground plane to work well.

Used both my NanoVNA to test the SWR and my high end RigExpert antenna analyzer and they both showed these antenna's are not 433MHZ. At 433MHZ they give a SWR of 10.5 + , I was able to get a SWR of 1.05 at around 386 MHZ. Needless to say, these are NOT safe to use at 433 MHZ and advise anyone not to make the mistake of purchasing these garbage antennas.

Llego como lo esperaba, totalmente recomendable. Gracias

My husband loved it.

I needed to repair the Wi-Fi antenna connection on my Pellet Grill and this application was the perfect fix and now my Grill Wi-Fi feature is back to working better than ever. I can see where this antenna kit would have multiple applications.

I'm using these with an ESP-32U, and they work flawlessly. No issues at all. Good strong signal.