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Home / Screws / 304 Stainless Steel Spring Plunger Screw Positioning Ball Pin Set Screw 12.9 Grade Steel Ball M2.5-16

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Screws
Origin -
Material 304 Stainless Steel Body, 12.9 Grade Steel Ball
Thread Size M2.5
Length Range 4mm to 16mm
Head Type Hex Socket (Allen)
Drive Size 1.5mm Hex Key
Spring Force Medium Duty
Finish Polished Stainless Steel
Application Positioning, Indexing, and Locking
Package Quantity 10 Pieces per Pack
Country of Origin China

6 reviews

A

Anonymous

Mar 28, 2026

Rating: 4/5

Solid hardware

These are small but mighty. The machining on the hex socket is clean with no burrs. Only giving 4 stars because I wish they came in a larger variety pack of lengths.

A

Anonymous

Mar 28, 2026

Rating: 4/5

Good quality, tight fit

Very well made. The spring tension is a bit stiff initially, but it loosened up after a few uses. Great for precise positioning tasks. Would recommend having a good quality hex key ready.

A

Anonymous

Mar 13, 2026

Rating: 5/5

Exactly as described

Dimensions were spot on. I ordered the M2.5 x 8mm size and it fit perfectly into my custom fixture. Fast shipping and well packaged to prevent damage.

A

Anonymous

Mar 13, 2026

Rating: 5/5

Great for automation projects

Using these in a robotic arm gripper mechanism. The consistent spring force helps with repeatable positioning. Very happy with the purchase.

A

Anonymous

Mar 07, 2026

Rating: 5/5

Perfect for my CNC jig

These plunger screws are exactly what I needed for my indexing plate. The 12.9 grade ball is hard enough to resist wear, and the stainless body prevents rust in my shop environment. Smooth action every time.

A

Anonymous

Mar 05, 2026

Rating: 5/5

Excellent durability

I've used these in a high-vibration application and they haven't backed out or failed. The combination of stainless steel and hardened steel ball is ideal for longevity.

5 FAQ

Q: Can these be used in outdoor applications?

A: Yes, the body is made of 304 Stainless Steel which offers good corrosion resistance, making them suitable for most outdoor environments.

Q: Is the spring force adjustable?

A: No, the spring force is pre-set at the factory to ensure consistent performance. It cannot be adjusted by the user.

Q: What size Allen wrench do I need for the M2.5 size?

A: For the M2.5 thread size, you will need a 1.5mm hex key (Allen wrench) to install or adjust the plunger.

Q: What is the hardness rating of the steel ball?

A: The ball is made from 12.9 Grade steel, which provides high hardness and wear resistance suitable for frequent indexing.

Q: Do you sell a replacement spring separately?

A: Currently, we only sell the complete plunger screw assembly. Individual springs are not available for separate purchase.

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