This is a mounting frame for the SBT-11 ( СБТ-11) Geiger-Müller tube. If you are a customer of IMPEXERIS ( http://www.ebay.com/sch/impexeris/m.html?_nkw=&_armrs=1&_ipg=&_from= ) on eBay you are entitled a free copy of this model. Please inquire directly by sending me a message. Alternatively you can send me an email . The address can be found in the first post on my blog here: http://arduino-geiger-pcb.blogspot.com