... borosilicate glass, double-alkali photocathode Diameter of 28.5mm(1.12 inch), nine stage, side-on photomultiplier tubes, ... glass, double-alkali photocathode Features: Diameter of 28.5mm(1.12 inch), nine stage, side-on photomultiplier tubes, ... turbidity meter, particle counter, biochemical analyzer, X-ray camera timer, optical density meter, optical properties to identify,replicate equipment. ...