use this adaptor for a phone or modem line addition or extension; in-line couplers are used for coupling two modular rj-45 cable together; the item named by manufacturer is rj coupler
Used on fnbe 21-pstn. 2.500" overall length 1.250" overall width pstn adaptor for sectera viper phone.provides an adaptor to connect the viper phone to the pstn analog network using an rj-11 cables.includes rj-11 cable, users manual