Type SF & SG Sight Plugs – Compact Level Indicators

The John Moncrieff Ltd Type SF & SG Sight Plugs are compact, low-cost assemblies that provide reliable and positive liquid-presence indication. Designed as screw-in plug-type level indicators, they feature high-quality heat-resistant glass for long service life and clarity.

Suitable for a wide variety of liquids including water, oils, lubricants, and chemicals, these versatile units are ideal for OEM and maintenance applications where simplicity, durability, and visibility are essential.

Example Applications

• Water and coolant systems
• Chemical equipment and process tanks
• Lubricant oil systems
• General liquid storage vessels

Key Features

• Compact Design: Simple screw-in construction for space-critical installations.
• Use Case: Ideal for compressor crank cases and machine housings.
• Pressure Rating: Up to 24 bar working pressure.
• Temperature Rating: Up to 180 °C.
• Construction Materials: Available in mild steel or stainless steel.
• Seal Options: Various seal materials to suit process compatibility.
• Thread Options: BSP, NPT, and Metric threads from ½″ to 2″.

Quality & Support

• ISO 9001 Certified: Produced under BSI-audited manufacturing and inspection procedures.
• Traceability: Material certificates and inspection reports available upon request.
• Technical Assistance: Support for thread specification and seal selection to match your medium and temperature.

The Type SF & SG Sight Plugs combine simplicity, durability, and clarity — the ideal fit-and-forget solution for machine housings and compact liquid systems.

Technical Specifications: