The PlayStation 2 Expansion Bay is a 3.5" drive bay introduced with the model 30000 and 50000 PlayStation 2 (replacing the PCMCIA slot used in the models 10000, 15000 and 18000, and removed with the slimline model 70000) designed for the network adaptor and internal hard disk drive (HDD). These peripherals enhance the capabilities of the PS2 to allow online play and other features that were shown at E3 2001. PlayStation 2 online functionality#Adapter and List of PlayStation 2 network games The Network Adaptor was released together with the launch of the PlayStation 2's online play service. Two models of the adaptor were available - one with a dial-up modem and an Ethernet jack for broadband Internet connection (mainly sold in North America), and one with only an Ethernet interface (sold in Europe and other regions). A start-up disc ("Network Access Disc") is included with the Network Adaptor and installs a file on the memory card for connection settings which are accessible by all but one Network Adaptor compatible game. Tony Hawk's Pro Skater 3, released in November 2001, supported the Network Adapter hardware, but not the software as it was not finalized until much later. The Network Adaptor also provides a Parallel ATA interface and a Molex disk drive power connector to allow installation of a 3.5" IDE hard disk drive in the expansion bay. As the two disk connectors are on separate circuit boards from the main Network Adaptor one, third party connector replacements including a SATA connector and SATA to IDE converter are available. Slimline PlayStation 2 models have an Ethernet port built-in (with some early North American models including an analog dial-up modem), but no official hard disk drive interface. The first slimline model (SCPH-70000) has a complete Network Adapter on board, and may be modified to add an external IDE connector board. From the SCPH-75000 series onwards, Ethernet functionality was integrated into the I/O processor (which was completely redesigned internally), completely removing the disk interface.