The cigarette lighter adapter provides the amplifier with the needed power. Wilson includes a 3-foot power cord in the box, but you can use your own USB/Mini-USB cable if you'd like. That's a nice design touch. We also like that the amplifier can charge your phone at the same time. You'll need to purchase optional adapter cables, but it's a convenient feature.
We tested the Mobile Professional while driving in our usual areas in San Francisco that have consistently poor reception. We noticed the biggest change when using AT&T and Sprint phones, though a T-Mobile device showed improvement as well. In most cases we had a stronger signal with fewer fade-outs and dropped calls. Problem areas weren't eliminated completely, but our conversations sounded better and we didn't encounter any interference.
It's important to note that individual results will vary; you shouldn't expect the Sleek to magically cure all your reception woes. Also, keep in mind that the Sleek needs at least a minimal signal to do its job. If we had no reception at all, we didn't see any difference in performance.
The Wilson Electronics Sleek supports CDMA and GSM in the 800 and 1900 bands. It won't support overseas GSM bands and Nextel's iDEN network, but those users can take advantage of other Wilson products.