I have several, ranging from $$ to $$$. Most bought on ebay. I live in Europe thus need them in case Russia or Ukraine decide to go crazy with nukes. Check ebay

I have several, ranging from $$ to $$$. Most bought on ebay. I live in Europe thus need them in case Russia or Ukraine decide to go crazy with nukes. Check ebay; GMC branded is decent Chinese one. Some of them also come with an espressif wifi card to send results to a webserver. https://www.gmcmap.com https://www.gmcmap.com. There are also Arduino kits that come with Soviet era geiger tubes (SBM 20).