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ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank - Threaded-Shank Three-Flute Countersinks
ROCKY MOUNTAIN TWISTThreaded-Shank Three-Flute Countersinks

ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank

The ROCKY MOUNTAIN TWIST Countersink: 100° is a threaded-shank three-flute countersink with a 1/2 in body diameter and a 1/4"-28 shank thread size. This black oxide cobalt tool, model 954CO5-21, is designed for…

SKU 3G-OTH-186100

Brand
ROCKY MOUNTAIN TWIST
Item
Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank
Category
Threaded-Shank Three-Flute Countersinks
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Technical Specifications

ROCKY MOUNTAIN TWIST
Manufacturer Part Number
954CO5-21
Type
Black Oxide Cobalt
Flute
3
Shank
1/4"-28
Body Dia
1/2 in
Shank Thread Size
1/4"-28
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ROCKY MOUNTAIN TWIST Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The ROCKY MOUNTAIN TWIST Countersink: 100° is a threaded-shank three-flute countersink with a 1/2 in body diameter and a 1/4"-28 shank thread size. This black oxide cobalt tool, model 954CO5-21, is designed for precise countersinking operations.

Frequently Asked Questions

What is a ROCKY MOUNTAIN TWIST 100° countersink used for?

This 100° countersink creates a conical recess for flat-head screws in metalworking. Its three-flute design and black oxide cobalt construction suit precision deburring and chamfering on ferrous materials, ensuring clean, chatter-free finishes in machining operations.

What are the specifications of the ROCKY MOUNTAIN TWIST 954CO5-21 countersink?

The ROCKY MOUNTAIN TWIST 954CO5-21 is a 100° countersink with a 1/2 in body diameter, 1/4"-28 threaded shank, and three flutes. It is made from black oxide cobalt for durability and heat resistance, designed for threaded-shank holders in industrial drilling applications.

Where to buy ROCKY MOUNTAIN TWIST countersinks worldwide?

3G Electric supplies ROCKY MOUNTAIN TWIST countersinks worldwide. As a global industrial sourcing partner, we handle logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on the 954CO5-21 or other threaded-shank countersinks.

How to select the right ROCKY MOUNTAIN TWIST countersink for my application?

Match the countersink angle (100°) to your screw head angle. Ensure the 1/4"-28 threaded shank fits your holder. For hard metals, black oxide cobalt provides wear resistance. Confirm body diameter (1/2 in) clears the hole size. 3G Electric can help you verify compatibility.

Used in

Common applications for ROCKY MOUNTAIN TWIST
Aerospace assembly — Rocky Mountain Twist NAS 965 Type D cobalt drill bits for drilling titanium airframe components
Automotive production line — Rocky Mountain Twist HSS threaded-shank drill bits for quick-change drilling in aluminum engine blocks
Heavy equipment maintenance — Rocky Mountain Twist cobalt drill bits for drilling hardened steel in field repair kits
Precision machining — Rocky Mountain Twist HSS drill bits in wire gauge sizes for jig and fixture drilling
Portable drilling operations — Rocky Mountain Twist threaded-shank drill bits for use with magnetic drill stands in structural steel fabrication

ROCKY MOUNTAIN TWIST Products

3G Electric supplies ROCKY MOUNTAIN TWIST threaded-shank three-flute countersinks. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank, Black Oxide Cobalt (MPN 954CO5-10). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.
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ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank, Black Oxide Cobalt (MPN 954CO5-30). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.
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ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank, Black Oxide Cobalt (MPN 954CO5-30). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.
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ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank (MPN 954HS5-30). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.
ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank, Black Oxide Cobalt (MPN 954CO5-40). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.
ROCKY MOUNTAIN TWIST
ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank, Black Oxide Cobalt (MPN 954CO5-40). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.
ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank (MPN 954HS5-21). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.
ROCKY MOUNTAIN TWIST
ROCKY MOUNTAIN TWIST Countersink: 100°, 3 Flute, 1/2 in Body Dia, 1/4"-28 Shank (MPN 954HS5-21). Key specifications — Shank Thread Size: 1/4"-28; Brand: ROCKY MOUNTAIN TWIST.