This timing machine will automatically calculate in real time for the following: -beat rate -Amplitude -beat error -beat number Power supply voltage is 100 V-240 V Features: Timegrapher NO.1900 LCD bigger Screen than no.1000; For almost mechanical watch and can work on coaxial watch; better view and easy to operate; Multi-purpose timegrapher, popular with the professional watchmakers as well as the watch collection. The measurement periods are selectable: 2s4s8s12s20s30s60s Automatic selection are available for the most common beat: 12000, 14400, 18000, 19800, 21600, 25200, 28800, 36000, 43200 Manual selection are available for the following beat: 3600, 6000, 7200, 7380, 7440, 7800, 9000, 9100, 10800, 11880,12000, 12342, 12480, 12600, 13320, 13440, 13500, 14000, 14040, 14160, 14200, 14280, 14400, 14520, 14580, 14760, 14850, 15000, 15360, 15600, 16200, 16320, 16800, 17196, 17258, 17280, 17786, 17897, 18000, 18049, 18514, 19332, 19440, 19800, 20160, 20222, 20944, 21000, 21031, 21306, 21600, 25200, 28800, 32400, 36000, 43200 Return Policy All of our items come with a 15-day free return policy. If you need to return, please contact us, let us know the detailed problem and send us some pictures for confirmation. We reserve the right to refuse any returns for objective reasons. Shipping Policy All of our items are shipped free with tracking numbers. Orders will be shipped within 3 working days upon receipt of payment. Most orders will be shipped within 1 working day. In most cases, shipping takes 8-12 working days.