Question

Grub screws are also known as

• A. Counter sunk head screw
• B. Pan head screw
• C. Headless screw
• D. Threadless screw

Hint:

Grub screw = set screw = headless screw. All three mean the same thing in mechanical design.

Answer 1

The Correct Option is C

A grub screw, or set screw, is a threaded fastener without a head.
It is fully threaded and is driven by an internal socket (such as a hex drive).
Because it is tightened completely inside the threaded hole, it does not have any external head that protrudes.
This makes it ideal for use where space is limited, or a smooth finish is needed on the outer surface.
Therefore, it is commonly known as a headless screw.
Other screw types like countersunk or pan head screws have visible heads, which grub screws lack.