Stainless Steel 3-Hole Thread Insert

Stainless Steel Three-Hole Insert is a threaded insert with three evenly distributed positioning holes. Using a dedicated installation tool, the positioning holes press into the base material to achieve mechanical locking for high-strength anti-loosening. Made from stainless steel, this insert offers excellent corrosion resistance, fits various internal and external thread specifications, and is widely used in applications with frequent vibration, high humidity, or corrosive conditions. It is a key component for improving the reliability and durability of threaded connections in low-strength materials.

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Product Features

Three-hole even distribution design: Three positioning holes evenly spaced at 120°, providing balanced load distribution and stable locking.
Wide size coverage: Suitable for standard thread sizes from M3 to M16, meeting various installation requirements.
Easy installation: Inserted and pressed into position using a dedicated tool without complex procedures.
High corrosion resistance: Made of stainless steel with excellent rust and corrosion resistance, suitable for humid or high-salt environments.
High connection strength: Forms an integrated interlocking structure with the base material, greatly enhancing the thread load capacity of low-strength substrates.

Applications

Enhance threads in soft base materials: Embed high-strength, wear-resistant stainless steel internal threads in aluminum, plastic, or wood.
Anti-rotation and anti-loosening: Base material is pressed into three holes during installation to form an internal lock, providing excellent vibration resistance.
Corrosion resistance: Stainless steel material suitable for humid, corrosive, or clean environments (e.g., food, medical equipment).
Easy installation: Self-tapping design; only a pre-drilled hole is needed for one-step installation.
Repair and pre-embed: Quickly repair damaged threaded holes or use as pre-embedded inserts to improve connection reliability.

Product Specifications

307/308 type(three hole type) self-tapping screw sleeve. 308 is a reinforced version of 307, both of which are only in length. This product has three self-tapping circular grooves, is easy to assemble, has high-strength threads, and is shock-resistant. Suitable for: aluminum alloy, cast iron, soft steel.

307/308 type (three hole type)		307 Type	308 Type	External thread	Reference drilling diameter		Minimum drilling depth
The metric system	English system	Length	Length		Aluminum alloy	Cast iron	307 Type	308 Type
M3-0.5	U#4-40	4	6	M5-0.6	4.6-4.7	4.7-4.8	6	8
M4-0.7	U#8-32	6	8	M6.5-0.8	6.0-6.1	6.1-6.2	8	10
M5-0.8	U#10-24	7	10	M8-1.0	7.4-7.5	7.6-7.7	9	13
M6-1.0	U1/4-20	8	12	M10-1.25	9.3-9.4	9.5-9.6	10	15
M8-1.25	U5/16-18	9	14	M12-1.5	11.1-11.3	11.3-11.5	11	17
M10-1.5	U3/8-16	10	18	M14-1.5	13.1-13.3	13.3-13.5	13	22
M12-1.75	U7/16-14	12	22	M16-1.75	15.0-16.2	15.3-15.5	15	26
M14-2.0	U1/2-13	14	24	M18-2.0	17.0-17.2	17.3-17.5	17	28
M16-2.0	U5/8-11	14	24	M20-2.0	19.0-19.2	19.3-19.5	17	28

Company Profile

Dongtai Jinzhize Metal Products Co., Ltd.

Dongtai Jinzhize Metal Products Co., Ltd. is a specialized manufacturing facility dedicated to threaded connection products for the automotive and aerospace sectors. We primarily produce Helical Wire Inserts, Self-Tapping Inserts, Key Locking Inserts, Threaded Adapters, Oil Plugs, as well as matching installation taps and tools.

Established in 2015, the company operates from a 10,000-square-meter-owned manufacturing plant equipped with hundreds of machine tools and automated production systems. Through years of development, we have built an experienced team of design, development, and production specialists, complemented by a rigorous quality management system and comprehensive after-sales service mechanism.

Our products are widely utilized in the automotive industry (including engines and transmissions for both passenger and commercial vehicles), the aerospace industry, and rail vehicle manufacturing.

With an annual output value of 153 million RMB in 2024, we possess the capability for a large-scale, stable supply. We are committed to providing customers with highly consistent, traceable products and reliable service support.