Headset Microphone with 3.5mm Jack

works great and cheaper than amazon site

Very nice product. Only improvement would be a better way to attach it to your waist.

Voice Booster Headset Microphone

The microphone headset initially works well but there needs to be reinforcements at the wiring connection points so that the wires inside the cord do not get damaged so easily. I have to replace the headset every year because with time something breaks down at these connection points creating a lot of static coming out of the speaker that is hung from my shoulder while starting track meets.