I don't recommend...
I ordered this doppler specifically because the website advertised a 2 MHz probe. I received a 3 and reached out asking if it was a mistake I received that one. They were pretty quick to reply, sent me a return label, and sent out a new one (which led me to believe it was a mistake) but when I opened it, it was the exact same 3MHz probe I already had. Apparently they didn't understand the problem. It was very disappointing. I emailed them again and never received another reply. The doppler itself is okay. I can usually hear a heartbeat on it but half the time I don't see it register on the doppler itself. Just based on the dishonest advertising I do not recommend.