HOW many serial 20X04 lcd work on arduino mega 2560

this is what i want to use
http://www.ebay.com/itm/Serial-IIC-I2C-TWI-2004-204-20X4-Character-LCD-Module-Display-For-Arduino-Blue-/180940569952?pt=LH_DefaultDomain_0&hash=item2a20e5fd60

many thanks