Self contained battery operated (6) AA batteries (not included) and AC adapter (included). Approximately 100 hours wil alkaline type cells. Full capacity push button tare. Switch selectable pound or kilogram display. All models can be wall or tower mounted. Rugged and durable and portable. 120 VAC, 50/60Hz, 1.5 watts. Accuracy +/-1 divisions. Pan size 11.8" x 15".