Spi 21-277-9 Flat Contact Point Dial Indicator

Product Description

The SPI 21-277-9 is a flat contact point designed for use with dial indicators in precision measurement applications. Machined from steel, this contact point features a 4-48 thread size and meets AGD Group 1 industry designation standards. With a contact point length of 0.5 inches and an overall length of 0.375 inches, it provides a stable, flat bearing surface for accurate dial indicator readings. This type of contact point is commonly installed by machinists, tool room technicians, metrology professionals, and quality control inspectors who require reliable, repeatable contact geometry during gauging operations.

The 21-277-9 flat contact point is suited for use across a wide range of dial indicator brands and models that accept standard 4-48 threaded contact points. It is a practical consumable or replacement accessory in any shop environment where flat-faced contact points are required for surface measurement, runout checks, or fixture-based inspection routines. The 0.5-inch diameter flat face distributes contact load evenly, making it appropriate for measuring flat or gently contoured workpiece surfaces.

Key Features

• Flat contact point style for stable surface-to-indicator contact
• Steel construction for durability in shop and metrology environments
• 4-48 thread size compatible with AGD Group 1 dial indicators
• Contact point length of 0.5 inches with overall length of 0.375 inches
• 0.5-inch diameter flat face for even load distribution on measured surfaces

Compatibility

Designed for use with dial indicators accepting a 4-48 threaded contact point, conforming to AGD Group 1 industry designation standards.

Installation Notes

Contact point replacement is a standard dial indicator maintenance task performed by machinists and metrology technicians. Before swapping contact points, ensure the dial indicator is removed from any active fixture or measuring setup. Use an appropriate spanner or contact point wrench to avoid damaging the indicator stem or thread. Do not overtighten the contact point, as this may affect spindle travel or damage the threaded stem.