Materials :
Best quality ss-420 stainless steel (investment castings) precisely heat-treated, ground & super- lapped to mirror finish.
quality :
100 % inspection for surface finish and size is controlled within ± 10 microns for each set of 3 (or 4 ) pieces

Packing :
sets of 3 or 4 pieces having size within ± 10 microns are packed separately.