In-line sight glass kit and assembly

An assembly (100) comprising;

• an assembly longitudinal axis (200), a tube body (4000), a first flange (2000), a transparent tube (5100), a first seal gasket (6200), a first attachment mechanism (1000), a first placement holder (6000);
• wherein
• the tube body has a tube body longitudinal axis (4030), a tube body first end (4400) which has a tube body first end contact surface (4450), a tube body second end (4500), a tube body inside diameter (4200), a window (4100);
• the transparent tube has a transparent tube first end (5100), a transparent tube first end contact surface (5200), a transparent tube second end (5150), a transparent tube second end contact surface (5250), a transparent tube inside diameter (5300), a transparent tube outside diameter (5250) which is less than the tube body inside diameter, a transparent tube longitudinal axis (5300),
• the first flange having a first flange longitudinal axis (2030), a first flange seal end (2100), a first flange connection end (2200), a first flange seal surface (2300), a first flange set surface (2500);
• and
• wherein the transparent tube is located inside the tube body;
• the first placement holder is separate from the first flange, is located between the tube body and the transparent tube, and is in contact with the transparent tube;
• the assembly longitudinal axis, the tube body longitudinal axis, the transparent tube longitudinal axis, and the first flange longitudinal axis are on substantially the same line;
• the tube body first end contact surface touching the first flange set surface, fixing a volume of the first seal gasket to prevent over or under torquing of the gasket;
• and
• a portion of the first seal gasket is under pressure and in contact with the first flange seal surface and the transparent tube first end contact surface.