The Casio SL-300SV-SK-UP is a no-frills pocket calculator which simply does what you need it to do. It is dual powered, with an auto power off feature to help save energy. A large 8-digit display and non-stick plastic keys make this a calculator which is both easy to read and easy to use. Other useful features include 3 key memory, a profit margin key, sign change and square root buttons, and a 3 digit comma marker.