Fowler 52-437-250-0 Alloy Steel Parallel Set 18 Piece

Product Description

The FOWLER 52-437-250-0 is an 18-piece alloy steel parallel set designed for precision machining and setup work in professional machine shops and tool rooms. Sold as 9 matched pairs, each parallel measures 6 inches in length and 1/4 inch in thickness, with heights ranging from 3/4 inch to 1-3/4 inch in 1/8-inch increments. The set is hardened to 52-58 HRC and holds a parallelism tolerance of 0.0002 inches, making it suitable for demanding workholding and inspection applications. Each parallel includes two drilled holes for easy handling and retrieval from vises. The set ships in a storage case.

This parallel set is used to support and elevate workpieces in milling vises, surface grinders, and inspection setups. The range of heights across 9 pairs gives machinists and toolmakers the flexibility to handle a wide variety of part geometries. Typical users include CNC and manual mill operators, grinder operators, and quality control technicians who need repeatable, accurate workpiece positioning. The 6-inch length provides stable support across standard milling vise jaws.

Key Features

• 18 pieces (9 matched pairs) covering heights from 3/4 inch to 1-3/4 inch in 1/8-inch increments
• Alloy steel construction hardened to 52-58 HRC for durability and wear resistance
• Parallelism tolerance of 0.0002 inches for precise workpiece positioning
• Each parallel features two drilled holes for magnet or hook retrieval from vises
• 6-inch length suits standard milling vise jaw widths
• Includes storage case to keep pairs organized and protected

Compatibility

Designed as a general-purpose precision parallel set for use with standard milling vises, surface grinders, and machine shop inspection fixtures requiring workpiece support in the 3/4-inch to 1-3/4-inch height range.

Installation Notes

Parallel sets are installed by machinists and toolmakers as part of workholding setup. Always clean vise jaws and parallel surfaces before use to ensure accurate seating. Never use parallels as striking surfaces or pry tools, as impact can compromise hardness and geometry. Inspect pairs periodically for wear or nicks that could affect parallelism accuracy.