I purchased this unit after trying another Callblocking unit. The problem with most Callblockers is that they require unknown callers to either leave a name or press a button to get through. As I run a Bed and Breakfast, I did not want to put callers off. I wanted something that would act as a normal phone for callers whilst blocking unwanted and anonymous calls and would work with my exsiting answer machine. This unit does this nicely.
Unwanted calls are rejected without the phone making a sound and potential guests are put through without any unwanted name or button pressing irritations. All witheld numbers are blocked and if a sales call gets through just press the button on the top of the unit and that number will be barred from then on. I'm not sure how effective the claim for blocking unwanted international sales call can be as they just show up on my CLI as international - so I dont see how this device can block them without blocking all international call - but time will tell. So far, this unit is almost perfect. Unfortunately, I do have one issue - the design. Why on earth did the designers decide to make the connection sockets on both sides rather than the rear of the device. Its inpossible to install this unit (albeit very small) without having unsightly wires showing. I would have also liked the block button to be able to be activated from any phone to save having to trek across to the unit - Therefore 4 stars rather than 5 stars.