I.Gabatarwar Samfuri:
Samfurin ya ƙunshi tushen samfurin da ƙayyadaddun girma goma daban-daban na farantin tsakiya, wanda ya dace da kauri (0.1 ~ 0.58) mm na samfurin, jimillar ƙayyadaddun bayanai 10, tare da faranti na tsakiya daban-daban, za su iya daidaitawa da kauri daban-daban na samfurin. Ana amfani da shi sosai a masana'antu da sassan duba takardu, marufi da ingancin samfura. Kayan aiki ne na musamman don gwada ƙarfin matse zobe na takarda da kwali.
U No.1 0.100-0.140 mm
U lamba ta 2 0.141-0.170 mm
U No.3 0.171-0.200 mm
U No.4 0.201-0.230 mm
U lamba 5 0.231-0.280 mm
U lamba 6 0.281-0.320 mm
U lamba 7 0.321-0.370 mm
U lamba 8 0.371-0.420 mm
U No.9 0.421-0.500 mm
U No.10 0.501-0.580 mm