user21539: Is Bitcoin Core the only protocol that uses these version numbers? 
Does anyone know what ABC and Unlimited use?
Is there a place where I can see the raw version numbers for each client easily?

user90837: Bitcoin clients no longer use version 2 or version 1 in the block headers. Block version is now defined as per BIP-9, and miners use specific bits in the block version number to signal their support for specific soft-forks in the bitcoin protocol. The top 3 bits of the blocks must be 001, so the range of actually possible nVersion values is from 0x20000000 to 0x3FFFFFFF, both inclusive.

21539: <p>Is Bitcoin Core the only protocol that uses these version numbers? </p>

<p>Does anyone know what ABC and Unlimited use?</p>

<p>Is there a place where I can see the raw version numbers for each client easily?</p>
 90837: <p>Bitcoin clients no longer use version 2 or version 1 in the block headers. Block version is now defined as per <a href="https://github.com/bitcoin/bips/blob/master/bip-0009.mediawiki" rel="nofollow noreferrer">BIP-9</a>, and miners use specific bits in the block version number to signal their support for specific soft-forks in the bitcoin protocol. The top 3 bits of the blocks must be 001, so the range of actually possible nVersion values is from 0x20000000 to 0x3FFFFFFF, both inclusive.</p>
