The CASIO AZ-255 is an eco-battery calculator specifically designed for learning. - Brand: CASIO - Model: AZ-255 - Function: STUDY CAL - Battery Type: ECO BATTERY - Accessories: Case Thank you for viewing. I have been using this for over 10 years. I am listing it for sale because I no longer have a use for it. The calculator has some scratches (see photo 4). The case's Velcro works, but it shows signs of use, with scuffs and stains (see photo 6). Please refrain from purchasing if you are sensitive to the condition, as it has been stored at home. Please understand that this is a used item before purchasing. It will be shipped via Yu-Packet Post.