Capable of operating at temperatures ranging from -40¡C to +85¡C, this two-member family of SMT quad transformer modules is for use in multi-port Ethernet applications where extreme temperatures can jeopardize a communications networkÕs reliability. Well- suited for use in stackable and modular 10/100Base-TX Ethernet switches, hubs and routers, the S558-5999-Z3 and -Z4 transformers are designed to interface with all major IC makersÕ transceivers and to support operation over unshielded twisted pair cables.The modules conform to IEEE 802.3u and ANSI X 3.263 standards, provide an isolation voltage o 2000VRMS, and use one (-Z3) or two (-Z4) common mode chokes on each of the devicesÕ eight channels to suppress EMI noise. The -Z3 and -Z4 40-pin quad transformers cost $3.56 and $5.10 each/10,000, respectively. BEL FUSE INC., Jersey City, NJ. (800) 235-3873.