It is also possible to pay for a subscription through the in game purchase of ETC (EVE time cards) using ISK (in game currency). This system was instituted by CCP and the transactions are protected by CCP staff.[34] This allows more advanced players able to generate the needed ISK to pay for their characters without any real money. The ETC sellers are also players and they gain in game ISK in trade for the purchase and resale of the ETC's. ETCs come in 30-50-90-100-180 day increments, and are treated just like normal subscriptions in every way.