... water position.It is also named: Reflex Gauge Glass, Sight glass, Reflex GlassesReflex sight glass, Spares For level GaugeThe category ... allow have palpable filaceous and pectinate stripe on the sight plane.4) Cockle: In the side face,don ... ’t allow have crack.6) Scrape: On the sight plane and in the 7.5mm to edge,the ... don’t allow more 2 strips.7) The sight plane must be polishing,and sealing side must ...