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ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21, 9/16" Overall Lg - Cobalt Threaded-Shank Drill Bits
ROCKY MOUNTAIN TWISTCobalt Threaded-Shank Drill Bits

ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21, 9/16" Overall Lg

The ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21 is a cobalt threaded-shank drill bit with a 0.1590-inch diameter and a 1/4"-28 thread size. It features a black oxide finish and conforms to NAS 965 Type D…

SKU 3G-OTH-195581

Brand
ROCKY MOUNTAIN TWIST
Item
Threaded Shank Drill Bit: #21, 9/16" Overall Lg
Category
Cobalt Threaded-Shank Drill Bits
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

ROCKY MOUNTAIN TWIST
Manufacturer Part Number
953CO21ST
Type
Black Oxide Cobalt
Overall Lg
9/16"

Technical Documents

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ROCKY MOUNTAIN TWIST Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21 is a cobalt threaded-shank drill bit with a 0.1590-inch diameter and a 1/4"-28 thread size. It features a black oxide finish and conforms to NAS 965 Type D specification, with an overall length of 9/16 inch.

Frequently Asked Questions

What is the ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit #21 used for?

This cobalt threaded-shank drill bit is designed for precision drilling in aerospace and industrial applications requiring NAS 965 Type D compliance. Its 1/4"-28 threaded shank allows secure mounting in tool holders, while the black oxide cobalt construction provides heat resistance and durability for hard metals.

What are the specifications of the ROCKY MOUNTAIN TWIST #21 drill bit?

The ROCKY MOUNTAIN TWIST #21 drill bit has a 0.1590-inch diameter, 9/16-inch overall length, and a 1/4"-28 threaded shank. It is made of black oxide cobalt and conforms to NAS 965 Type D specification. The manufacturer part number is 953CO21ST.

Where to buy ROCKY MOUNTAIN TWIST threaded shank drill bits worldwide?

3G Electric supplies ROCKY MOUNTAIN TWIST threaded shank drill bits worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on the #21 bit (MPN 953CO21ST).

How to select the correct ROCKY MOUNTAIN TWIST threaded shank drill bit?

Select based on required diameter, thread size, and material. The #21 bit has a 0.1590-inch diameter with a 1/4"-28 thread, suitable for NAS 965 Type D applications. For hard metals, choose black oxide cobalt. Ensure the threaded shank matches your tool holder's thread specification.

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 cobalt threaded-shank drill bits. 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 Threaded Shank Drill Bit: #21, 1-1/4" Overall Lg, Black Oxide Cobalt (MPN 953CO21SS)
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ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21, 1-1/4" Overall Lg, Black Oxide Cobalt (MPN 953CO21SS)
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ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21, 2-1/8" Overall Lg, Black Oxide Cobalt (MPN 953CO21LS)
ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #22, 9/16" Overall Lg, Black Oxide Cobalt (MPN 953CO22ST)
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ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #22, 9/16" Overall Lg, Black Oxide Cobalt (MPN 953CO22ST)
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ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #22, 1-1/4" Overall Lg, Black Oxide Cobalt (MPN 953CO22SS)
ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #22, 2-1/8" Overall Lg, Black Oxide Cobalt (MPN 953CO22LS)
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ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #22, 2-1/8" Overall Lg, Black Oxide Cobalt (MPN 953CO22LS)

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