Spi 91-353-3 Feeler Gauge 0.0015 in Parallel Leaf Steel

Product Description

The SPI 91-353-3 is a single parallel-leaf feeler gauge used to measure small gaps and clearances with precision. The leaf measures 0.0015 inches thick, 0.5 inches wide, and 12 inches long, making it suitable for checking tight tolerances in mechanical assemblies, valve clearances, bearing fits, and similar applications. Constructed from high carbon steel, the leaf resists flex and wear under repeated use. HVAC technicians, mechanics, and machinists reach for individual feeler gauge leaves when a specific thickness is needed for a recurring measurement task without carrying a full set.

This gauge is well suited for residential and light commercial HVAC service, general mechanical work, and precision measurement tasks in shop or field environments. The 12-inch parallel leaf length provides consistent contact across the full measurement area, reducing the chance of a false reading caused by a tapered or short blade. Technicians use leaves in this thickness range when checking burner electrode gaps, contactor gaps, or other fine clearances that demand accuracy at the sub-thousandth level.

Key Features

• 0.0015-inch thickness for sub-thousandth gap measurement
• Parallel leaf style maintains uniform thickness along the full 12-inch length
• High carbon steel construction for durability and consistent stiffness
• 0.5-inch leaf width provides adequate contact surface for accurate readings
• 12-inch length accommodates deep or hard-to-reach measurement points

Compatibility

Designed as a general-purpose parallel-leaf feeler gauge suitable for gap and clearance measurement across HVAC, mechanical, and machining applications where a 0.0015-inch leaf thickness is required.

Installation Notes

A licensed technician or trained mechanic should verify that the correct gauge leaf thickness matches the specification called out in the equipment service manual before taking a measurement. Power down or de-energize any equipment and allow moving parts to come to a complete stop before inserting the gauge leaf into a gap. Clean the gauge leaf and mating surfaces of debris or oil buildup that could affect reading accuracy. Do not force the leaf into a gap narrower than the rated thickness, as this can permanently deform the steel and compromise measurement accuracy on future use.