Brass Thumb Screws

Brass Flat Knurled Thumb Screws (DIN 653)

Brass thumb screws feature a low-profile, knurled head for easy hand tightening without tools. The wide grip and decorative brass finish make them ideal for precision adjustment, equipment access and vintage or visible assemblies. Available in M3 to M8 and lengths 6mm to 40mm, with specials to order.

These Brass Flat Knurled Thumb Screws (DIN 653), sometimes known as Thin Type Knurled Thumb Screws, feature a wide, shallow cylindrical head with a knurled outer edge. This design allows the screw to be tightened or loosened by hand, with no tools required.

Brass thumb screws are commonly used in mechanical assemblies, fixtures, equipment panels and any application that requires regular adjustment or maintenance access. The larger head diameter provides fine control when positioning or securing components.

Brass offers several advantages, including:

Corrosion and water resistance for long-lasting performance
Anti-bacterial properties, suitable for medical or clean environments
A warm, decorative, gold-like appearance
Suitable for some exterior use due to its resistance to rust

Our brass thumb screws are supplied as standard in thread sizes M3 to M8 and lengths from 6mm to 40mm. Optional thread locking patches can be added to help prevent loosening from vibration.

These thumb screws can also be supplied in A1, A2 and A4 stainless steel, titanium and phosphor bronze.

We also supply Knurled Reduced Thread Captive Thumb Screws for applications requiring retained fasteners.

Non-standard sizes, materials and finishes can be manufactured to order, including small batch production and custom parts made to drawings. Minimum order quantities apply.

Technical Data & Available Sizes
Thread Diameter (d1)	M3	M4	M5	M6	M8
d2 nom. (mm)	12	16	20	24	30
h nom. (mm)	2.5	3.5	4	5	6
l2 (mm)	2	3	3	4	5
Available Sizes (l1)	M3	M4	M5	M6	M8