Keo 919-000-251 Countersink Set 5 Pc Cobalt Steel

Product Description

The KEO 919-000-251 is a 5-piece cobalt steel countersink set designed for right-hand countersinking operations in metal, composite, and hard materials. The set covers a head diameter range of 5/16 to 1 inch with a consistent 100-degree included angle across all five tools, making it suitable for a variety of standard fastener preparations. Shanks run straight and range from 1/4 to 3/8 inch in diameter. Each countersink carries a bright, uncoated finish and is manufactured from cobalt steel for added heat and wear resistance compared to standard high-speed steel tooling. A plastic storage case is included.

This set is suited for machine shops, maintenance facilities, and fabrication environments where multiple countersink sizes are needed in a single kit. Applications include deburring drilled holes and preparing seating surfaces for flat-head fasteners in ferrous and non-ferrous materials. The range of overall lengths, from 1-5/8 to 2-5/8 inches, accommodates use in standard drill chucks and drill press setups. Single-end construction keeps the tools straightforward to index and replace individually.

Key Features

• 5-piece set covering 5/16 to 1 inch head diameter range
• 100-degree included angle on all countersinks for standard flat-head fastener applications
• Cobalt steel construction for improved heat resistance and tool life
• Straight shank, 1/4 to 3/8 inch diameter, compatible with standard drill chucks
• Bright uncoated finish for clean performance across a range of workpiece materials
• Includes plastic storage case to keep the set organized between uses

Compatibility

Designed as a general-purpose countersink set for use in drill presses, lathes, and hand-held drill drivers accepting straight-shank tooling in the 1/4 to 3/8 inch range.

Installation Notes

These countersinks are installed by machinists and tool-and-die professionals using standard drill chucks or collet-style holders. Secure the shank fully before operation and confirm the workpiece is clamped to prevent movement. Select the appropriate countersink size for the intended fastener head to achieve proper seating depth. Inspect cutting edges for wear before use on hard materials to avoid chatter or premature tool failure.