Used to inspecion verticality and parallelism as well as absolut 90 degree measuring

Specification(mm)	SquarenessBetween adjacent measruing surface		Straightness of measuring surface		Parallelism between opplsite measuring surface
	Grade(um)
	00	0	00	0	00	0
160x160	2	4	0.8	1.7	2	4
200x200	2	4	0.9	1.8	2	4
250x250	2.2	4.5	1	2	2.2	4.5
630x400	2.6	5.2	1.1	2.3	2.6	5.5

Granite Squares Rulers