Just got in my new order from Sportsman's Guide which included a 90 pill bottle of 32.5 mg KI. While I was checking out when ordering this product they did the usual thing of "people who bought this also bought ......". Lo and behold there was a 717 CD Radiation detector for $99 (cheaper if you belong to the Buyer's Club). So I picked one up to fill that big hole in my preps when it comes to radiation. Basically on this unit the geiger-mueller tube is completely enclosed in the base of the machine. It runs on one D cell battery which means I'll have to buy a new rechargeable battery set-up as the one I have is for AAA & AA batteries. All in all I'm very pleased with this acquisition.

BTW for our purposes 1 Roentgen (R) is approximately equal to 1 Rem (Roentgen equivalent man). I won't go into the conversions of Grays and Sieferts. I stick to what I learned originally and screw the SI units!