Like most headsets for desk phones, the CS50 has a base unit that plugs into your phone's handset port. If you wish to use the handset, you can also plug the receiver back into the base unit, which conveniently doubles as a charger. The headset itself weighs less than an ounce, and it feels like next to nothing when it's on your person. You can wear the headset with either an ear clip or a headband, and the two connect to the unit with a separate plastic attachment. Both are comfortable, although you might prefer going with the headband if you put on and remove the headset often. However, we found the attachment piece to be rather flimsy, breaking off after just six weeks of use.
The Plantronics CS50 is similar to most office headsets in that it lacks a button that allows you to answer your phone from afar; you have to be close to your desk to pick up incoming calls. If you want to answer remotely, you'll have to shell out an additional $79 to get the lifter accessory that fits under your handset; this item literally lifts the phone off the hook so that you can answer the call via the headset's on/off key. Regardless, you'll have to be near your desk unit to make calls because there's no keypad on the headset.
The CS50 works on the old-fashioned 900MHz radio band, which gives it two big advantages: range and clarity. In our tests, the headset stayed connected to its base unit when in use from more than 100 feet away. Plantronics asserts the CS50 has a range of 300 feet, but we weren't able to establish that distance from the base without leaving the building. Plus, since the CS50 doesn't operate on the newer 2.4GHz band, it won't suffer from interference generated by Wi-Fi networks, Bluetooth components, or microwave ovens.
The Plantronics CS50's sound quality is excellent, although fine-tuning it to match your desk phone is a trying process. You can make three adjustments on the base unit, and there's a volume control on the headset itself. We noticed a slight echo in our system at first, and we had to fiddle quite a bit with all the dials before vanquishing the annoyance.
Plantronics rates the CS50's talk time at 8 hours. Our tests proved that the company is not far off; we coaxed a little more than 7.5 hours from the headset.