方形角尺Granitesquaresrulers規格Type(mm)相鄰兩測量面垂直度Squarenessbetweenadjacentmeasuringsurfaces測量面直線度Straightnessofmeasuringsurface相對測量面平行度Parallelismbotweenopplsitemeasuringsurface精密等級Precisiongrade( m)OO級O級OO級O級OO級O級160*160240.81.724200*200240.91.824250*2502.24.5122.24.5300*3002.65.21.12.32.65.5用于垂直、平等度檢測，并可作為900絕對測量基準。Oninspectionlfverticalityandparallelismaswellasabsolure90 measuring.