Set of 4 M30 × 1.5 oil level sight glasses for oil tanks, gearboxes, pumps, compressors

M30 x 1.5 Sight Glass Compatibility: Compatible with oil tanks, gearboxes, pumps, and air compressors that use M30 x 1.5 threaded ports, allowing for quick visual checks in workshop, factory, or garage systems. Oil Level Indicator Window: The clear plastic lens displays the presence of oil and the approximate level at a glance, supporting routine checks and preventative maintenance without opening the tank or interrupting equipment operation. M30 x 1.5 Threaded Sight Cap: The screw-on design fits standard M30 x 1.5 holes; the low profile aids in tight layouts; the sealed body helps reduce leakage when properly installed with appropriate thread sealant. Machine Maintenance Accessory: Helps monitor the fill level to prevent low oil or overflow. Suitable for use on gearboxes, pumps, and compressors in industrial lines, repair shops, farms, and small equipment rooms. Easy-to-install oil viewer: clean the port, apply the appropriate sealant, tighten by hand, then tighten with a wrench. Position the window vertically for an accurate reading. Ideal for routine inspections at home, in the garage, or in the factory.