Spi 91-400-2 Feeler Gage 0.20mm Parallel Leaf High Carbon Steel

Product Description

The SPI 91-400-2 is a single-leaf feeler gage designed for precise gap measurement in mechanical assembly, engine work, and machine setup applications. The leaf measures 0.20 millimeters (mm) in thickness, 0.5 inches wide, and 12 inches long, providing the reach needed to check clearances in confined spaces. Constructed from high carbon steel, the leaf resists flex and wear across repeated use cycles. This tool is used by machinists, engine builders, HVAC technicians, and millwrights who require accurate, repeatable gap readings without relying on digital instrumentation.

The 91-400-2 is suited for residential and commercial maintenance environments where component clearances must be verified to specification. Common applications include valve lash adjustment, bearing clearance checks, spark plug gap verification, and alignment work on rotating equipment. The parallel leaf style delivers consistent width along the full 12-inch length, making it practical for slots, flanges, and tight bearing journals where a tapered leaf would give ambiguous readings.

Key Features

• 0.20 mm leaf thickness for fine-tolerance gap measurement
• Parallel leaf style maintains consistent 0.5-inch width across the full length
• 12-inch length provides reach into deep or recessed clearance points
• High carbon steel construction resists deformation and surface wear
• Single-leaf format for direct, unambiguous gap reading

Compatibility

Designed as a general-purpose feeler gage leaf suitable for mechanical assembly, engine service, and precision maintenance tasks requiring a 0.20 mm gap measurement reference.

Installation Notes

Feeler gages are hand tools and require no installation. Insert the leaf into the gap to be measured with light, consistent hand pressure — the leaf should slide with slight resistance when the correct clearance is achieved. Keep the leaf clean and free of burrs; a damaged or corroded leaf will produce inaccurate readings. Store flat to prevent permanent set in the steel.