Spi 21-273-8 Flat Contact Point Dial Indicator

Product Description

The SPI 21-273-8 is a flat contact point designed for use with dial indicators in precision measurement applications. Machined from black oxide steel, this contact point features a 4-48 thread size and measures 3/4 inches in length with a 3/16-inch diameter tip. The black oxide finish provides corrosion resistance in shop environments. It conforms to AGD Group 1 industry standards, making it a direct-fit replacement for standard dial indicator contact points. Metrology technicians, machinists, and quality control inspectors are the typical users of this type of accessory.

This contact point is intended for use with AGD Group 1 dial indicators in precision measurement setups such as surface plate inspection, fixture gauging, and machine tool verification. The flat contact style is well suited for measurements on flat or broad surfaces where a rounded or pointed tip would introduce error. It is a common consumable in tool crib and QC department inventories.

Key Features

• Flat contact point style for accurate measurement on flat workpiece surfaces
• Black oxide steel construction for durability and corrosion resistance
• 4-48 thread size for standard AGD Group 1 dial indicator compatibility
• 3/4-inch contact point length with 3/16-inch tip diameter
• Conforms to AGD Group 1 industry designation

Compatibility

Designed for use with AGD Group 1 dial indicators that accept a 4-48 threaded contact point.

Installation Notes

Installation is performed by machinists or metrology technicians using standard hand tools. Power down or de-energize any automated fixture or CNC setup before swapping contact points to avoid unintended movement. Thread the contact point in by hand to avoid cross-threading, then snug with a wrench — do not overtighten, as the fine 4-48 thread is easily damaged. Verify indicator zero and calibration after replacing any contact point.