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3.5mm Headphone To RJ9/RJ10/RJ22 Phone Adapter

Usually ships within 24 hours

Product Description

  • Convert 3.5mm Smartphone plug to single 4P4C RJ9/RJ10 handset plug.
  • Save money by buying a smartphone headset, or using your existing one with your Aastra phone's handset jack.
  • Reduce clutter with single headset.
  • Does not work with RJ11 jack, which is wider than your handset or 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.
  • Works best with 4-pole (TRRS) headsets 

This amazing adaptor converts the standard 3.5mm smartphone plug to an Aastra RJ9, RJ10, or RJ22 handset plug, allowing you to use your favorite smartphone headset with your Aastra office phone. The adapter outputs binaural sound for stereo headsets, meaning you will hear sound out of both ears. The adapter cable is approximately five inches long.


**Works best when paired with an amplifier**



Incompatible Phones:

Avaya 1100, 1200, 1600, 2000, 4600 and 9600 series

Cisco phones

Nortel 1140T and Visa 350

Polycom phones

Shortel IP 230

Uniden Dect2088, TRU9496

Western Electric 6250


Compatible Phones:

*This list is not all inclusive*

Aastra/Packet8/8x8 480e, 480i, 53i, 55i, 57i, 57iCT, 6753i, 6755i, 6757i, 9112i, 9133i, 9143i, 9480i

Allworks 9212

AltiGen IP Phone 500, 510, 600, 705, 710, 720

Avaya 4500 Series IP

ESI 48-Key IP Feature Phone and 48-Key Digital Feature Phone

GE Model 2-9451


Lucent 8410D

Mitel IP 40XX, 41XX, 5000, 50XX, 5140, 52XX, 53XX, 5550

NEC Dterm Series E

Norstar T7316E, M3904

Nortel IP 1120E IP, 1140E IP, 1150E IP, 1230, i2002 and i2004

Nortel Meridian Norstar Northern Telecom

Panasonic Hybrid

Plantronics T10

Possum Sero

Shoretel ShorePhone IP models


Splicecom PCS 520

Talkswitch IP Phone, TS-600


3COM 3102, 3103

Compatible Amplifiers:

Plantronics S-12, M22, A20, MX10, TSB, AP15

Have More Questions? Visit our Frequently Asked Questions

Here are what customers are saying about our products:

"Excellent deal, fast shipping! This little connector has improved my job 100%."

"It makes life so much easier!!!!"

"Good service and excellent quality."


Product Videos

iPhone and Smartphone Headset to Office Phone - 3.5mm to RJ9 00:38

Connect a 3.5mm headset (iPhone, smartphone, and more) to a standard office phone. Available at

  • Headset Buddy Video Thumbnail Preview Image
    iPhone and Sma...
    Connect a 3.5mm headset (iPhone, smartphone, and more) to a st...

Warranty Information

Free returns, always!

We have a 30-day, no-questions-asked return policy for all of our products as well as a one-year, 100% Satisfaction guarantee; we’ll replace your HeadsetBuddy for free within the first 12 months.