Spi 91-386-3 Feeler Gauge 0.033 in Parallel Leaf Steel

Product Description

The SPI 91-386-3 is a single parallel-leaf feeler gauge used to measure precise gaps and clearances in mechanical assemblies. Manufactured from high carbon steel, this gauge leaf measures 0.033 inches thick, 0.5 inches wide, and 12 inches long. The parallel leaf design maintains a consistent cross-section along the full length, ensuring accurate readings from tip to heel. HVAC technicians, machinists, and general maintenance professionals use feeler gauges to verify valve clearances, set igniter gaps, check compressor tolerances, and confirm bearing fits. This is a single leaf sold individually.

Feeler gauges are a standard hand tool across HVAC, refrigeration, and mechanical trades. The 0.033-inch leaf is commonly used for igniter gap settings, valve tappet clearances, and tight-tolerance mechanical fits in both residential and light commercial equipment. The 12-inch length provides reach into confined assemblies without bending the leaf. The 0.5-inch width offers a stable contact surface for reliable seating against mating components.

Key Features

• 0.033-inch thickness for precise gap measurement at that dimension
• Parallel leaf profile maintains uniform thickness along the full 12-inch length
• High carbon steel construction resists deformation under repeated use
• 0.5-inch leaf width provides stable, flat contact against measured surfaces
• 12-inch length allows reach into deep or confined component clearances

Compatibility

Designed as a standard parallel-leaf feeler gauge suitable for gap and clearance measurement tasks in HVAC, refrigeration, machining, and general mechanical maintenance applications.

Installation Notes

Feeler gauges are used by HVAC technicians, machinists, and maintenance trades as a measurement instrument, not an installed component. Power down or lock out any equipment before inserting a feeler gauge into rotating or energized assemblies. Do not force the leaf into a gap tighter than the leaf thickness, as this can bend or permanently deform the leaf and cause inaccurate readings. Handle the leaf edges with care, as high carbon steel edges can be sharp.