The two most common configurations are base/mobile (vehicle mounted), and portable (handheld). Generally for scanners the RF performance is about the same. The base/mobile style scanners generally have a better speaker (but usually benefit from an external speaker), and are more suitable for permanent mounting in a vehicle or at a desk. Portable scanners are generally smaller, easier to carry, and can run on batteries, but most have weak speakers and some are not as durable.