Pan Head Self Tapping Screw

BIS Certfied   DIN 7981 C  /  ISO 7049  ·  Phillips Cross Drive  ·  White Zinc & Stainless Steel  ·  ST2.9 to ST6.3

The pan head self tapping screw confirming to DIN 7981 C / ISO 7049 is a fully threaded fastener with a cross recessed Phillips drive and a gimlet point that cuts its own thread into pre-drilled sheet metal, plastic, fibre glass and wood — no nut, no pre-tapped hole required. The broad, flat-underside pan head distributes clamping load evenly without digging into the material surface. Excel Trading Corporation stocks this in BIS Certified mild steel white zinc plated and stainless steel SS304 (A2).

Specifications

  • Bullet Icon Standard: BIS Certified DIN 7981 / ISO 7049
  • Bullet Icon Drive: Phillips cross recess (PH)
  • Bullet Icon Point: Gimlet point — Form C (sharp)
  • Bullet Icon Thread: ISO 1478 — fully threaded, coarse pitch
  • Bullet Icon Material: Mild steel white zinc plated & Stainless steel A2 (SS304)

Applications

  • Bullet Icon Thin gauge sheet metal fabrication and enclosures
  • Bullet Icon Plastic panels, electrical boxes and junction boxes
  • Bullet Icon Fibre glass, resinous plywood and composite boards
  • Bullet Icon Automotive interior trim and body panels
  • Bullet Icon HVAC ducting, switchboard assembly and cable trays
Pan Head Tapping Screws

Available In

Steel

White Zinc

Stainless Steel

Stainless Steel

Available Sizes — DIN 7981 C / ISO 7049

All sizes below are stocked in mild steel white zinc plated and stainless steel SS304 (A2). The pilot hole diameter should be slightly smaller than the screw's core diameter — refer to the recommended pilot hole column for each size. Use the smallest pilot hole that allows clean installation for maximum thread engagement.

Size (ST) Outer Ø (mm) Head Ø (mm) Head Height (mm) Pilot Hole (mm) Common Lengths (mm)
ST 2.9 2.9 5.6 2.1 2.2 6.5  ·  9.5  ·  13  ·  16
ST 3.5 3.5 7.0 2.6 2.7 9.5  ·  13  ·  16  ·  19  ·  25
ST 4.2 4.2 8.4 3.1 3.2 9.5  ·  13  ·  16  ·  19  ·  25  ·  32  ·  38
ST 4.8 4.8 9.5 3.55 3.7 9.5  ·  13  ·  16  ·  19  ·  25  ·  32  ·  38  ·  45
ST 5.5 5.5 10.8 4.0 4.3 13  ·  19  ·  25  ·  32  ·  38  ·  45
ST 6.3 6.3 12.0 4.6 5.0 16  ·  19  ·  25  ·  32  ·  38  ·  45  ·  50

Material Options

Mild Steel — White Zinc Plated

Case Hardened · ISO 2702 · Standard Grade

Case hardened low carbon steel with bright white zinc plating. The hardened thread cuts cleanly through sheet metal, plastic and composite board on the first drive. Zinc plating provides corrosion protection for indoor and dry environments. The most economical choice for general sheet metal fabrication, switchboard assembly and HVAC applications.

Best for: Sheet metal · Switchboards · Plastic enclosures · HVAC ducting · General fabrication

Stainless Steel — A2 / SS304

DIN EN ISO 3506 · A2-70 · Passivated

304-grade austenitic stainless steel (A2), passivated finish. Fully corrosion resistant for outdoor, coastal, humid and marine environments. Non-magnetic, aesthetically clean finish. Slightly softer than hardened mild steel so should not be driven into very hard substrates. SS316 (A4) available on request for aggressive chemical environments.

Best for: Outdoor enclosures · Coastal installations · Food equipment · Marine panels · Signage

Which Material Should You Choose?

Click your environment to get the right recommendation.

Quick Specifications

ST2.9–6.3

Size Range

DIN 7981

Standard (= ISO 7049)

Phillips

Drive Type

MS + SS

Materials Available

Installation Tips

  • ▸ Always drill a pilot hole — never drive a self tapping screw into undrilled material. An undersized pilot creates excessive torque and risks cam-out or head stripping.
  • ▸ Use the correct pilot hole size from the table above — too large reduces thread engagement; too small risks splitting plastic or snapping the screw.
  • ▸ Drive at moderate speed — high RPM causes heat build-up in plastic that strips the thread before full seating.
  • ▸ Do not overtighten — the pan head's flat underside seats cleanly when hand-tight. Over-driving distorts thin sheet metal and reduces holding strength.

Frequently Asked Questions

What is a pan head self tapping screw?

A pan head self tapping screw has a broad cylindrical head with a flat underside that seats flush against the material surface, distributing clamping load without cutting into the workpiece. The self tapping thread cuts its own thread into a pre-drilled hole in sheet metal, plastic, fibre glass or wood — no nut or tapping tool required. Standardised under DIN 7981 and ISO 7049 with Phillips cross drive.

What is the difference between DIN 7981 and ISO 7049?

DIN 7981 is the German standard and ISO 7049 is the international equivalent for the same pan head cross recessed self tapping screw. The dimensions, thread form (ISO 1478) and mechanical requirements are identical — they are interchangeable. Both designations are widely used and accepted in India. Excel Trading Corporation stocks screws compliant with both standards.

What pilot hole size do I use?

Refer to the Pilot Hole column in the size table above. As a general rule, the pilot hole should be slightly smaller than the screw's outer thread diameter — typically equal to the core diameter. For softer materials like plastic and wood, use a tighter pilot for more thread engagement. For harder sheet metal, the listed pilot holes give clean threading without excessive torque.

When should I use stainless steel instead of mild steel?

Use stainless steel (A2/SS304) whenever the screw will be exposed to moisture, outdoor conditions, coastal air or food contact. Zinc plated mild steel corrodes over time in these environments — the zinc layer is not sufficient for prolonged wet exposure. For aggressive chemical environments, request SS316 (A4). For all indoor, dry and sheltered applications, zinc plated mild steel is the correct and more economical choice.

Where can I buy DIN 7981 pan head self tapping screws in Bangalore?

Excel Trading Corporation stocks BIS Certified pan head self tapping screws confirming to DIN 7981 C / ISO 7049 in mild steel white zinc plated and stainless steel SS304 at our Kumbarpet store in Bengaluru. We supply to sheet metal fabricators, switchboard manufacturers, HVAC contractors and general industry across Karnataka and India-wide. Call +91-9448239476 or email info@exceltrading.in for pricing and availability.