The Seiko 1E20 quartz watch movement is a ladies two hand caliber with hour and minute measuring 4¼ lignes or 9.00 × 9.40 mm with a thickness of 2.60 mm and total height of 3.35 mm. This 5 jewel movement uses hand sizes 90/45 operates on a 335 battery and is supplied with stem part number 354 930 with a 0.60 mm tap 13 thread.