High Wycombe, Buckinghamshire-based Walters International Ltd has a battery-backed, mains operated laptop offered in a 20Mb version for UKP2,020, and a 40Mb version priced at UKP2,190: both have a 14 by 13 by 4 footprint, an 80286 processor running at switchable speeds of 12MHz or 6MHz, and a standard 1Mb of memory expandable to 4Mb; the liquid crystal display screen has a resolution of 720 by 400, and the laptop has a battery life of 30 minutes for the 20Mb, 60 minutes for the 40Mb, with replacement batteries costing the user UKP50.