Use for adjusting and checking horizontal and vertical surfaces and shafts.Sensitivity .0002" per 10", .0005" per 10", .02mm per 1000mm, .05mm per 1000mm.2 Side with flat bearing surfaces and 2 sides with flat plus Vee bearing surfaces.Heat insulating top handle.PRECISION FRAME SPIRIT LEVELSInchDim..0002" per 10" Model No..0005" per 10" Model No.6x6"639-3906639-39168x8"639-3908639-391810x10"639-3910639-392012x12"639-3912639-3922MetricDimensions.02mm per 1000mm Model No.0.05mm per 1000mm Model No.150x150mm639-3706639-3806200x200mm639-3708639-3808250x250mm639-3710639-3810300x300mm639-3712639-3812