ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21, 2-1/8" Overall Lg
The ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21 is a high-speed steel threaded-shank drill bit with a black oxide finish. It features a 0.1590-inch diameter, a 1/4"-28 thread size, and a 2-1/8" overall length…
SKU 3G-OTH-192831
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Product Description
The ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit: #21 is a high-speed steel threaded-shank drill bit with a black oxide finish. It features a 0.1590-inch diameter, a 1/4"-28 thread size, and a 2-1/8" overall length, meeting NAS 965 Type B specifications (MPN 953HS21LS).
Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.
Frequently Asked Questions
What is the ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit #21 used for?
This high-speed steel drill bit with a 1/4"-28 threaded shank is designed for precision drilling in aerospace and industrial applications where secure mounting in a threaded holder is required. The black oxide finish reduces friction and improves wear resistance. It meets NAS 965 Type B specifications for controlled-depth drilling in metal assemblies.
What are the specifications of the ROCKY MOUNTAIN TWIST Threaded Shank Drill Bit #21?
The ROCKY MOUNTAIN TWIST drill bit (MPN 953HS21LS) has a #21 wire gauge diameter of 0.1590 inches, a 1/4"-28 threaded shank, and a 2-1/8" overall length. It is made from high-speed steel with a black oxide finish and conforms to NAS 965 Type B standards for aerospace fastening applications.
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 since 1990, we handle full logistics, customs clearance, and delivery to your facility. Contact our team to source the NAS 965 Type B compliant #21 drill bit (MPN 953HS21LS) for your operations.
How to select the correct ROCKY MOUNTAIN TWIST threaded shank drill bit?
Select based on thread size (1/4"-28 for this #21 bit), diameter (0.1590 inches), and overall length (2-1/8"). Ensure the shank matches your tool holder's thread. For aerospace work, verify NAS 965 Type B compliance. ROCKY MOUNTAIN TWIST bits are precision-ground for tight tolerances. Consult your application's hole-depth and material requirements.
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3G Electric supplies ROCKY MOUNTAIN TWIST high-speed steel threaded-shank drill bits. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.















