a stream of data, and, in the case of CatFur, could add a short chat message to the sender in the middle of the one-way file transfer. Many bulletin board systems (BBSs) running CatSend and then CatFur were set up to transfer warez. One BBS program that worked around this limitation was Tele-Cat II, which used escape sequences to switch between 202 half-duplex 1200 bits/second mode (for sending data) and Bell 103 full-duplex 300 bits/second mode (for receiving user input). The 202 CatFur protocol could only be used if both ends of the communication were using Apple-CAT II modems. In addition, the Apple-CAT II had the ability to support CCITT v.21 and CCITT v.23, the European standards for 300 and 300/1200 baud operation (as opposed to the normal Bell 103/202 versions). Though no known applications took advantage of this facility, it was possible to modify certain software such as ASCII Express by use of a hex editor to take advantage of this feature. Novation also released a full-duplex Bell 212-compatible expansion board known as the Novation 212 Expansion Card, which plugged into the Apple II motherboard as well as an existing Apple-CAT II via a ribbon cable. The card was very expensive and rarely seen. Novation also created an 'Expansion Pack' or external breakout box that would connect to the large pin header on the top middle of the card. This item allowed easy external access to the built-in serial port, phone line and handset connections. Due to its cost at the time, the item is very rare. The Apple-CAT II was popular with phone phreakers for its high half-duplex 1200 bit/s speed and its ability to detect various tones. It also had the ability to generate tones directly into the phone line. Several specialized applications such as TSPS, The Cats Meow and Phantom Access were used to mimic standard telephone sounds such as standard numeric DTMF dial tones as well as blue box tones, ringing (both American and International), dial tones, call waiting alerts, busy signals, 2600 Hz tones, and other effects such as payphone sounds. Due to these and other features, the Apple-CAT II could be used as a black box, red box, hacking tool, answering machine, war dialer, voice simulator, voice distorter, etc. BYTE criticized Novation, stating that "the company's literature should be very explicit" about the modem's inability to communicate at 1200 baud with Bell 212