Spi 20-977-5 Ball Needle Contact Point Dial Indicators

Product Description

The SPI 20-977-5 is a ball needle contact point designed for use with dial indicators in precision measurement applications. Machined from chrome alloy steel, this contact point features a 4-48 threaded shank and measures 0.75 inches in contact point length, with a ball diameter of 0.1563 inches. It meets AGD Group 1 industry designation standards, making it a direct-fit replacement or accessory for standard dial indicator setups. Machinists, tool and die technicians, and quality control professionals use this type of contact point when a spherical tip is required for accurate surface contact on irregular or curved workpieces.

This contact point is suited for precision measurement tasks in machine shops, manufacturing facilities, and inspection environments. The ball needle style provides consistent point contact on contoured surfaces where a flat or standard tip would introduce measurement error. It threads directly onto compatible dial indicators using the standard 4-48 thread, which is common across AGD Group 1 indicator bodies.

Key Features

• Chrome alloy steel construction for durability and wear resistance
• Ball needle tip style for accurate contact on curved or irregular surfaces
• 4-48 threaded shank compatible with AGD Group 1 dial indicators
• Contact point length of 0.75 inches for standard reach applications
• Ball diameter of 0.1563 inches for precise point contact
• Meets AGD Group 1 industry designation

Compatibility

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

Installation Notes

Installation is performed by machinists or metrologists and requires no special tools beyond those standard to dial indicator maintenance. Thread the contact point carefully into the indicator spindle by hand to avoid cross-threading, then snug to seat without overtightening. Always zero the indicator after changing contact points to account for any difference in tip geometry or length.