The Proxmark is an RFID swiss-army tool, allowing for both high and low level interactions with the vast majority of RFID tags and systems world-wide.
There are few Promark Devices, and you can find them at the offical website. I personally use the device at the picture above, you can get one at
it's cheap and suites my needs
The RFID tags i use are duel band tags 13.56Mhz and 125KHz