1.Operated by dry batteries 2.Optional AC adaptor 3.Simple piece counting function 4.Stainless steel weighing pan available SPECIFICATIONS Capacities & Weigh/Count Pan Dimensions JKH-500......500g.x0.1g. 140mm.x140mm. JKH-1000......1000g.x0.2g. 140mm.x140mm. JKH-4000.......4000kg.x1g. 140mm.x140mm. Units...............g, oz, ct, pcs/kg, g, lb/oz ,pcs 6 AA size bateries or AC adapter (option)