An assembly comprising; an assembly longitudinal axis , a tube body , at least a first flange , a transparent tube , at least a first seal gasket , and at least a first attachment mechanism ; wherein the tube body has a tube body longitudinal axis , a tube body first end which has a tube body first end contact surface , a tube body second end , a tube body inside diameter , and a window ; the transparent tube has a transparent tube first end , a transparent tube first end contact surface , a transparent tube second end , a transparent tube second end contact surface , a transparent tube inside diameter , a transparent tube outside diameter which is less than the tube body inside diameter, and a transparent tube longitudinal axis ; the first flange having a first flange longitudinal axis , a first flange seal end , a first flange connection end , a first flange seal surface , and a first flange set surface ; and wherein the transparent tube is located inside the tube body; 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; and at least 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. an assembly longitudinal axis , a tube body , at least a first flange , a transparent tube , at least a first seal gasket , and at least a first attachment mechanism ; wherein the tube body has a tube body longitudinal axis , a tube body first end which has a tube body first end contact surface , a tube body second end , a tube body inside diameter , and a window ; the transparent tube has a transparent tube first end , a transparent tube first end contact surface , a transparent tube second end , a transparent tube second end contact surface , a transparent tube inside diameter , a transparent tube outside diameter which is less than the tube body inside diameter, and a transparent tube longitudinal axis ; the first flange having a first flange longitudinal axis , a first flange seal end , a first flange connection end , a first flange seal surface , and a first flange set surface ; and the tube body has a tube body longitudinal axis , a tube body first end which has a tube body first end contact surface , a tube body second end , a tube body inside diameter , and a window ; the transparent tube has a transparent tube first end , a transparent tube first end contact surface , a transparent tube second end , a transparent tube second end contact surface , a transparent tube inside diameter , a transparent tube outside diameter which is less than the tube body inside diameter, and a transparent tube longitudinal axis ; the first flange having a first flange longitudinal axis , a first flange seal end , a first flange connection end , a first flange seal surface , and a first flange set surface ; and wherein the transparent tube is located inside the tube body; 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; and at least 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. <EOS>