I. Application Fields & Product Positioning

This product is a Phillips countersunk self-drilling screw with stop lugs. Its countersunk design allows the screw head to sink fully into panels after installation for a smooth, protrusion-free surface.

The stop lug structure controls drilling depth to prevent penetration of thin sheets. It is widely used for light steel keels, interior sheet metal, furniture hardware and thin steel plate assembly for doors and windows, applicable to interior decoration and electromechanical equipment assembly.

Equipped with an integrated drill tip that eliminates pre-drilling, it secures both steel and wood substrates and sells well in hardware and building material markets worldwide.

II. Raw Materials & Production Processes

Manufactured from premium carbon steel, it delivers sharp drilling performance and resists tip chipping.

The complete production process includes twelve procedures: raw material rough drawing, annealing, phosphating, fine drawing, cold heading, lug & drill tip forming, thread rolling, tail shaping, thermal refining treatment, galvanizing, washer assembly and packaging.

The integrated stop lugs automatically limit drilling depth once the set penetration is reached. The Phillips cross recess fits screwdriver bits smoothly without slipping during installation. The matte, low-oil black phosphate surface will not stain panel coatings, ensuring cleaner indoor assembly.

III. Core Product Advantages

Stop Lugs Prevent Over-Drilling

Dual stop lugs on the shank halt drilling at the designated depth, effectively avoiding punctured thin iron sheets and gypsum boards to reduce construction waste.

Concealed Countersunk Installation

The tapered countersunk head embeds fully into substrates after tightening, creating flat panel surfaces for superior visual results in ceiling and interior decoration projects.

IV. Quality Control, Warehousing & Supporting Services

All sizes are kept in permanent stock with shipments dispatched within 48 hours. We accept sample orders and full export bulk orders.

Every batch undergoes pre-delivery sampling inspection covering drill tip hardness, lug forming dimensions, thread integrity and phosphate coating quality to eliminate defective products.

We can deliver complete fastener sets bundled with standard countersunk self-drilling screws and self-tapping screws for one-stop fastener sourcing. Custom extended-length variants can be produced against customer samples, with stable production capacity to guarantee long-term supply.