The LSP101 Series low pressure aluminum sight plug inserts through a clearance hole and utilizes a lock nut assembled from within the reservoir to seal on a flange gasket. A clear glass sight provides good open view visibility with options to further enhance visibility by accessorizing the sight plug with combinations of reflector and float ball options. Access to inside of reservoir is required to secure the lock nut. Box quantities may apply. Standard Features: Sight diameters from .55 to 1.88 inches Clear glass sight Body machined from aluminum bar stock Pressure & Temperature Ratings: Maximum operating temperature up to 180°F (82°C). For applications requiring maximum operating temperatures in excess of 180°F (82°C), consult factory for available options. Pressure ratings vary by sight plug size, refer to spec sheet for complete details. Caution: Do not use an impact wrench to install sight plug. Not recommended for steam applications. Scratched glass significantly reduces the pressure rating of the sight plug.