Countersunk concrete screws are thread-cutting screw anchors with a flat countersunk head. They cut their own thread into a pre-drilled hole in concrete or masonry, and the head sits flush with the fixture, so they are used wherever a raised head would be in the way.
Linkworld supplies CSK concrete screws in carbon steel and stainless steel, with zinc, yellow zinc, black, hot-dip galvanised and Ruspert finishes. We pack in bulk cartons or in your own branded packs, and sizes outside the common range can be made to your drawing or sample.
CSK Concrete Screw Specifications
| Specification | Configuration |
|---|---|
| Product | Countersunk concrete screw / screw anchor |
| Material | Hardened carbon steel; stainless steel |
| Common diameters | M6, M8, M10 and M12 |
| Common lengths | 50 to 150 mm |
| Head | Countersunk, flush finish |
| Drive | Internal hex or Torx |
| Finish | Zinc, yellow zinc, black, hot-dip galvanised or Ruspert |
| Base materials | Concrete, solid brick and block |
| Packing | Bulk cartons, own-brand boxes, buckets and small packs |
Other sizes and finishes can be made to drawing or sample.
Where CSK Concrete Screws Are Used
- Timber to concrete bottom plates, battens and packers fixed flush
- Door and window frames fixed into concrete and masonry openings
- Brackets and plates where the fixture must stay flat
- Handrails and stair parts base plates on concrete
- Formwork and site fixings removable fixings on building sites
Choosing a Countersunk Concrete Screw
- Diameter and length: choose the length to cover the fixture thickness plus the embedment the manufacturer or designer requires.
- Finish: zinc for dry interior work, galvanised or Ruspert for outdoor use, stainless steel for coastal or wet areas.
- Drive: internal hex is common; Torx gives better bit grip on long screws.
- Base material: concrete, brick and block behave differently. Tell us which one you are fixing into.
Anchor selection for structural fixings should follow the project design.
Common Purchasing Mistakes
Choosing a countersunk head for a thin fixture. The head needs enough fixture thickness to sit flush. Use a hex head where the fixture is thin.
Ordering by diameter only. Give the length too, based on fixture thickness and embedment.
Using zinc screws outdoors. Zinc plated screws suit interior work. Specify galvanised, Ruspert or stainless for outdoor jobs.
Mixing drives under one code. Hex and Torx versions of the same size should have separate item codes.
What to Send with Your Enquiry
| Item | What to tell us |
|---|---|
| Size | Diameter and length; a drawing or sample for other sizes |
| Material | Carbon steel or stainless steel |
| Finish | Zinc, yellow zinc, black, galvanised or Ruspert |
| Drive | Internal hex or Torx |
| Quantity | Quantity for each size |
| Packing | Bulk carton, own-brand box, bucket or small pack |
| Destination | Destination port |
Packing and Supply for Distributors
We pack concrete screws in bulk cartons for trade distribution, or in your own branded boxes, buckets and small packs for retail. Each size can carry its own label. For customers who plan several deliveries through the year, we offer free warehouse storage and staged shipments.
Work With Linkworld
Linkworld has more than 20 years of fastener export experience and runs its own cold heading workshop. Our own QC team checks thread, head form, hardness and coating in our inspection room before every shipment. We make screws to drawing or sample, so special lengths, drives and finishes are welcome.
Frequently Asked Questions
What are countersunk concrete screws used for?
They fix timber, frames, brackets and plates to concrete or masonry where the screw head must sit flush with the fixture.
What sizes are CSK concrete screws?
M6, M8, M10 and M12 in lengths from about 50 to 150 mm are the common sizes. Other sizes can be made to drawing.
Do concrete screws need a plug?
No. A concrete screw cuts its own thread into a pre-drilled hole, so no plug or sleeve is needed.
Which finish is best for outdoor concrete screws?
Galvanised or Ruspert coated screws are common for outdoor use, and stainless steel for coastal or wet areas.
Can you supply countersunk concrete screws with Torx drive?
Yes. We supply internal hex and Torx drive versions.
Looking for countersunk concrete screws in your own sizes or packs?
Send the sizes, finish, quantity and packing you need through the enquiry form below, and our team will reply with the options that fit your range.
Send an Enquiry
Send a drawing, sample or clear reference photo. Add the quantity and application if available, and we can start from the information you already have.