HP 39gs, Pocket, Graphing, 15 digits, Flash, Battery, Silver HP 39gs. Form factor: Pocket, Type: Graphing. Digits: 15 digits, Display number of lines: 10 lines, Display number of characters: 33. Memory registers: 70, Storage media type: Flash. USB port, USB 2.0 ports quantity: 1. Power source: Battery. Product colour: Silver