CTG's line of Null Modem serial cables allows two DTE or DCE devices to communicate with no conflict in data transmission. The transmit and receive signals are crossed to ensure proper data transmission. CTG's inexpensive, high-quality cables deliver the data for you quickly and reliably over short distances (less than 100 feet). Each of our Null Modem cables are designed with a rugged, overmolded construction that provides added strain relief and a solid connection each time. As always, the cables are foil shielded for protection from EMI/RFI interference caused by surrounding office equipment and flourescent lights. Available in a wide array of stock lengths and gender combinations, our offering also allows connections to DB9 (AT) or DB25 (PC) serial ports. Cables in female-to-female versions are typically connecting two PC serial ports. Don't forget, custom lengths are our specialty.