APC 940--1525A UPS Communications Smart-UPS Signalling Serial RS-232 Cable DB9 to RJ45 (RJ50) - Same as 940-1525C and 940-0625A But a Longer Cable APC 940-1525A UPS Communications Smart-UPS Signalling Serial RS-232 Cable DB9 to RJ45 (RJ50) Cable Lenght: 15ft. Same as 940-0625A but a Longer Cable to allow you to send signal over longer distance Compatible with Smart-UPS 5G(Serial) SMX750, SMX1000, SMX1500 Compatible with Smart-UPS 4.5G(Serial) SMT750, SMT100, SMT1500, SMT2200, SMT3000 Rugged, over-molded construction that provides extra strain relief and a solid serial connection.