
Bitcoin XT is an implementation of a Bitcoin full node, based upon the source code of Bitcoin Core with a focus on upgrades to the peer to peer protocol. By running it you can opt in to providing the Bitcoin network with additional services beyond what Bitcoin Core provides, including bigger blocks.
It is built by taking the latest stable Core release, applying a series of patches, and then doing deterministic builds so anyone can check the downloads correspond to the source code.
%AppData%\Bitcoin\data%AppData%\Bitcoin\wallet.dat