[HozayBuck]

The high price of those units made me shy away as I want to have a few detection units.
I went with the credit card type units for $30 each. Here's what I'm referring to.
RADTriage Radiation Detector | No batteries | Instant detection

I'd need one that talked to me, having on in my wallet wouldn't help me, I need a beep or chirp or a "HEY STUPID!! RUN !!" sound...