Came exactly as advertised, very sensitive to even background radiation. Has a backlight. One thing is it does not click when a particle is detected, it beeps. It is definitely a tonal beep. With headphones it is a click however.

Cons would be that it's not rugged. It feels delicate. The switches protrude and I feel like I could break them off if I were to pack it in a bag without a case. There is an option for it to come with slide switches instead on their main site.

This is an excellent and accurate tool for measuring radiation.
- This Geiger Counter was purchased primarily for disaster/catastrophic situations and I was initially disappointed to discover it wouldn't work with Nickel Metal Hydride rechargeable 9 volt batteries, e.g. "Supreme Power" brand. These freshly-charged batteries test at 8 volts when a voltage meter is applied to the contacts without load. I did some research and ordered batteries with a higher voltage. I am pleased to confirm the GCA-07W Professional Geiger Counter works with "Powerex" 9 volt batteries. My VOM (again "no load") reads slightly over 10 volts when applied to freshly charged Powerex batteries. I am glad I waited to paste this eval as l now rate it five stars.
- Incidentally, when I noted this battery problem last month, I sent an email to the company with an inquiry about this issue and, though they didn't have a (this!) suggestion, they did get back to me promptly which speaks well of their support efforts. We also discussed a more robust case and switches which they have considered too; it would add significantly to the price, perhaps as much as 50% more!
UPDATE Aug 15, 2018: (This update is written in response to some recent questions and answers that came to my attention.) I store my device in a double Faraday Cage. This makes it substantially more EMP resistant. I also bought an uranium ore sample to test calibration. I will probably have it professionally re-calibrated in 3-5 years to see if it is stable in storage.

This is a nifty gadget. It can use a 9V battery for portability. The detachable wand is good for really zeroing in on the sample you want to test. It is sensitive to even low levels of radioactivity, such as what one might find in some granite, or an old piece of uranium glass. It has a backlight feature so you can read it in the dark. It makes a beeping noise with each ionization event. This Geiger counter lacks the classical ticking noise, but otherwise this is a great product that can shed light on any nuclear curiosities one my have.

I like this instrument. It has a good range of detection especially for a field survey instrument. The unit is compact but the switches on front will make it important to have a good case before it goes into a backpack. I was told by a technician that the saturation point was at its upper limit of 10,000 cpm and that recovery of the tube was nearly instant once removed from the radiation field. Other words, it would not handle high energy nuclear radiation (>1 R/hr).

My daughter asked for this for Christmas and she absolutely loved it! She is a collector of depression glass and fiestaware and was more than thrilled with the product. Love the way it looks and how it feels in hand. Comfortable and simple! Love it.