Convert two 3.5mm plugs to single 4P4C RJ9/RJ10 Cisco headset plug
Works great with Cisco IP office phones with a RJ9 headset jack
Does not work with RJ11 jack, which is wider than your headset jack (6 positions vs. 4). RJ11 jack is what is in the wall. RJ9, RJ10, RJ22 are what is on your phone handset or headset.
Use your existing i-Phone/ i-Pad, or similar TRRS headset with your C i s c o-based phone
PC Stereo Headset Dual 3.5mm to RJ Plug for most Phones as below Description compatible list.

Technical Details

Product Details

Product Dimensions

Package Dimensions
Width : 2.7 inch
Height : 0.4 inch
Length : 3.8 inch

Item Weight: 0 ounce (View shipping rates and policies)
Shipping Weight: 0 ounce (View shipping rates and policies)

ASIN : B01NA9KGG6