Stainless Countersunk Self-Tapping Screws — 60-Piece Assortment (M4.2 × 10/12/16/20/25/32 mm)

Flush-mount countersunk self-tapping screws in corrosion-resistant stainless steel for clean installs in wood, thin metal, and plastics. The sharp tapping thread bites quickly, while the flat head sits level with the surface for a smooth, professional finish. A practical 60-piece kit covering six popular sizes for assembly, repair, and DIY projects.

• Countersunk head sits flush—no snagging or proud heads
• Self-tapping thread simplifies installs; pilot often optional*
• Stainless steel for indoor/outdoor corrosion resistance
• Multi-material: wood, sheet metal (thin), plastics, composites
• Six sizes from 10 to 32 mm length—ready for mixed tasks

Technical Specifications

Item Type	Self-tapping screw assortment (countersunk / flat head)
Material	Stainless steel (corrosion-resistant)
Nominal Diameter	M4.2
Lengths Included	10, 12, 16, 20, 25, 32 mm
Head Style	Countersunk (flat)
Drive	Phillips/Pozi style (varies by batch)
Thread	Sharp self-tapping thread for quick bite
Pack Quantity	60 pieces (6 sizes assorted)
DIY Category	Woodworking / General assembly
Chemicals of Concern	None declared
Model	60pcs
Origin	Mainland China
Brand	Conversions Tech

Package Contents

• 60 × stainless countersunk self-tapping screws (M4.2 × 10/12/16/20/25/32 mm assorted)

Install Notes: Self-tapping threads can be driven directly in many materials. For hardwoods, dense plastics, or thin sheet metal, a small pilot improves finish and reduces splitting/bulging. Drive until the head seats flush—avoid over-torque that can strip threads. Maintain edge distance for best holding power.

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FAQs

What does “countersunk” mean?

The flat head is designed to sit flush with the surface so hardware doesn’t protrude after installation.

Do I need to pre-drill?

Often not. For hardwood, thin sheet metal, or brittle plastics, a pilot hole improves results and reduces splitting.

What materials can I fasten?

Wood, thin sheet metal, plastics, and many composites. Choose pilot size appropriate to the substrate density.

Are these suitable outdoors?

Yes—stainless steel offers good corrosion resistance for general outdoor use. For marine/coastal exposure, consider marine-grade fasteners.

What drive type do these use?

Phillips/Pozi style heads (varies by batch). Use a matching bit to minimize cam-out.

What’s included in the 60-piece kit?

Six lengths of M4.2 (10/12/16/20/25/32 mm) assorted to a total of 60 pieces.

Will the head sit below the surface?

It seats flush. You can lightly countersink the hole in hard materials for a perfectly level finish.

How do I avoid stripping?

Use the correct bit, firm axial pressure, and moderate speed. Stop once the head seats—don’t over-torque.

Can I use them with anchors?

Yes—pair with suitable wall anchors if fastening into drywall, block, or masonry.

Magnetic or non-magnetic?

Stainless grades may be slightly magnetic depending on composition and work-hardening; magnetism is not a performance defect.

Are they food-safe?

These are general-purpose fasteners; for food-contact assemblies, use certified hardware per your standard.

What bit size should I use?

Match the bit to the head (Phillips/Pozi). Using the correct profile reduces cam-out and improves finish.

Do they work in aluminum sheet?

Yes—use a small pilot and moderate torque to form clean threads without galling.

Can I remove and re-use them?

Yes, but each re-install may reduce holding power in soft substrates. Use fresh locations for critical joints.

Will they crack plastics?

Use a pilot in brittle plastics and drive slowly to control heat and stress.

What projects is this kit best for?

Cabinetry, fixtures, hardware mounting, panel work, small repairs, prototyping, and general DIY.

Any safety notes?

Contains small parts—keep away from children. Wear eye protection when drilling/driving.

Why are some photos enlarged?

Images may be shown larger for clarity. Refer to the listed sizes for actual dimensions.

What if the pack count varies slightly?

Minor count variance can occur with small packs; we aim to meet or exceed the stated total.

Do you offer bulk packs?

Yes—contact Conversions Tech for contractor quantities or size-specific packs.