This is a SATO Model NSII-BQ Sigma II barograph.  It's manufactured by Sato Keiryoki Mfg Co in Japan and is shown in the 2010 and 2014 SATO catalogs available on this website.  It has a quartz clock drive which is switch-selectable with 31 day, 7 day, or 1 day rotation. It uses two C batteries.  It was also available with a spring-driven clock.  I believe charts are still available for it, I have the 31 day chart.  It has a range of 950 to 1040 hPa.  It's about 13 inches wide and 10.5 inches tall.

Go to SATO Keiryoki catalog webpage.

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