This is the Jabra QD (Quick Disconnect) to RJ-9 coil cable for Cisco IP 69xx, 794x, 796x, and 797x, 89xx Phones:

some compatible Cisco phones: 6921, 6941, 6945, 6961, 7931G, 7940, 7940G, 7941, 7941G, 7942G, 7945, 7945G, 7960, 7960G, 7961, 7961G, 7965G, 7970, 7970G, 7971G, 7975G, 7985G*, and 8900, 9900 Series (8941, 8945, 8961, 9951, 9971)

If you have a Cisco SPA models (SPA 5XX, SPA 9XX), click here instead

This cable is functional equivalent to the GN Netcom 8800-02