The ‘v1’ and ‘v2’ coins were released after the initial ‘v0.1’ test batch. This coin uses a slightly higher denomination of fifty millibitcoins, which is the equivalent of 0.05 BTC.
Worth mentioning is that the v0.1, v1, and v2 coins are the first coins to contain no numeric private key, with a QR code instead being utilized. This has served as inspiration for both bhCoin and Titan Bitcoins. Another notable factor is that these coins often have ‘firstbits’ of only five or six characters, instead of the traditional eight.