Serene Business Phone Amplifier (UA50) - Hands-Free Speakerphone for Conference Calls, Office & Home Use - Crystal Clear Sound for Professional Meetings & Remote Work

I tried a few other amplifiers that I had used at another job and those did not work on the new work phone so I tried this and it works very well. I can actually hear all the callers which is very important for my job! The sounds is very clear and easy to change from handset to headset you do have to push down the headset botton when you want to hear from the headset I was used to this with my old ampliefiers so once you get used to switching back and forth you are good to go. The volume gets pretty loud I use it at about 40 -50 % capacity if you will and this is perfect with a normal phone I was maxing the phone volume out and still not hearing properly so this does boost the volume as stated. Please note you have to buy the 50 ( the more expensive one) if you want it to work with a headset but the cost is not bad considering.