Grainger Key Locking Insert: Heavy Wall, 4 Keys, 7/8"-9 Int Thrd Sz, 1 1/4"-12 Ext Thrd Sz
The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil-spec insert with 4 keys, plain finish, and a 10-pack quantity. It features a 7/8"-9 internal thread size and a 1 1/4"-12 external thread size, with coarse…
SKU 3G-OTH-531730
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Product Description
The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil-spec insert with 4 keys, plain finish, and a 10-pack quantity. It features a 7/8"-9 internal thread size and a 1 1/4"-12 external thread size, with coarse thread type, 18-8 material grade, and compliance with MS51831-210. Compatible with a 1-1/4"-12 tap and a 1-11/64 in drill bit, it meets external thread fit 2A and internal thread fit 3B.
Frequently Asked Questions
What is an APPROVED VENDOR Key Locking Insert used for?
This heavy-wall key locking insert is used to repair or reinforce stripped threads in metal assemblies, particularly in aerospace, defense, and industrial equipment. The 4 keys lock the insert into the parent material, preventing rotation under vibration. It meets mil-spec MS51831-210 for critical threaded connections.
What are the specifications of the APPROVED VENDOR 217-076310 Key Locking Insert?
This 10-pack insert has a 7/8"-9 internal thread and a 1 1/4"-12 external thread, both coarse. It is made of 18-8 stainless steel with a plain finish, heavy wall, and 4 keys. It meets MS51831-210, requires a 1-11/64 in drill bit, and has external thread fit 2A and internal thread fit 3B.
Where to buy APPROVED VENDOR Key Locking Inserts worldwide?
3G Electric supplies APPROVED VENDOR key locking inserts worldwide. As a global industrial sourcing partner, we handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on the 217-076310 10-pack or other mil-spec inserts.
How to install a heavy-wall key locking insert?
Drill the hole to the specified size (1-11/64 in for this insert), tap it with a 1-1/4"-12 tap, then drive the insert into the tapped hole using a compatible installation tool. The 4 keys will engage the parent material to lock the insert in place. Follow MS51831-210 guidelines for torque and final inspection.
Grainger Products
3G Electric supplies Grainger mil. spec. key-locking inserts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

