Datexx DB-403 3-Memory Checkbook Calculator Keeps track of a personal budget or income and expense records in in one of the 3 independent memories Solar powered so it will work anywhere, anytime. Built-in long life lithium battery maintains your memory files Soft black leatherette wallet holds the checkbook calculator plus your checks, bank receipts, credit cards and more Lock mode lets you set a password in order to protect your data from unauthorized access