Product Advantage: Large Storage; maximum storage reaches 100000 codes; memory 4M can be extended to 8M. Scan storage and total scans counting. Long communication distance; 150-300m indoor and 300-500m outdoor. Supporting network construction; 1 base to 254 readers or 15 bases to 1 reader; ID display. Repeated code detection; no messy-code programmed. Free of charging trouble; battery lasts 6-10 hours after full charged; base functions as receiver and charger. Long lifespan battery; demountable and replaceable. - See more at: http://www.bestbarcodescan.com/product-detail/rd-2018-wireless-laser-barcode-scanner/#sthash.vMtaZOSw.dpuf