ISO / DIN Slotted Machine Screws Reference

ISO 1580 / DIN 85 Slotted Pan Head Screws

Precision metric slotted pan head machine screws available in steel (4.8, 8.8), stainless steel (A2-70, A4-70), and brass. Engineered for electrical enclosures, control panels, instrumentation, and light mechanical assemblies across UAE & GCC.

What Are ISO 1580 & DIN 85?

The global metric standard for slotted pan head machine screws used in threaded holes or paired with metric nuts.

ISO 1580 (and its German standard predecessor DIN 85) specifies the dimensions, mechanical properties, and tolerances for metric slotted pan head machine screws. These screws feature a slightly rounded, low-profile dome head with a flat bearing surface that offers excellent clamping area without damaging softer mating surfaces. The standard covers two primary drive variations:

Slotted Drive (ISO 1580)

ISO 1580 / DIN 85

Standard single-slot drive designed for installation using standard flat-blade screwdrivers. Sizes range from M1.6 to M10.

Drive: Slotted (Straight) | Thread: Metric Coarse (ISO 261)

Cross Recess Variant

ISO 7045 / DIN 7985

Identical pan head profile featuring a Phillips or Pozidriv cross-recess drive for power-driver assembly lines.

Drive: Phillips / Pozidriv | Thread: Metric Coarse (ISO 261)

Engineering Advantage: The wide flat bearing surface under the pan head distributes clamping load evenly, preventing surface distortion in electrical control panels, plastic housings, sheet metal covers, and precision instruments.

Property Classes, Materials & Finishes

Material Grades & Options

  • Property Class 4.8 Carbon Steel: Economical low-carbon steel for standard light-duty mechanical and electrical applications. Typically zinc-plated.
  • Property Class 8.8 High Tensile Steel: Medium carbon steel quenched and tempered for applications requiring higher shear and tensile holding force.
  • Stainless Steel A2-70 (AISI 304): Corrosion-resistant austenitic stainless steel for indoor/outdoor electrical cabinets, food machinery, and architectural fittings.
  • Stainless Steel A4-70 / A4-80 (AISI 316): Marine-grade stainless steel with molybdenum for harsh coastal UAE environments, chemical processing, and desalination plants.
  • Brass (CuZn): Non-magnetic and highly conductive alloy ideal for electrical terminals, switchgear, and decorative assemblies.

Mechanical Properties (ISO 898-1 / ISO 3506-1)

Property Class 4.8 Steel Class 8.8 Steel Stainless A2-70 / A4-70 Brass (CuZn)
Tensile Strength (Rm)400 MPa800 MPa700 MPa≥ 380 MPa
Yield Strength (Rp0.2)320 MPa640 MPa450 MPa≥ 200 MPa
Elongation (A)≥ 14%≥ 12%≥ 0.4d≥ 15%
Surface FinishZinc Plated / PlainZinc Plated / BlackPlain (Passivated)Plain / Nickel Plated

Chemical Composition Standards

Grade Carbon (C) Manganese (Mn) Phosphorus (P) Sulfur (S) Key Elements
Class 4.8 / 5.8≤ 0.55%≥ 0.25%≤ 0.050%≤ 0.060%Low Carbon Steel
Class 8.80.25 – 0.55%≥ 0.35%≤ 0.025%≤ 0.025%Medium Carbon Steel
Stainless A2 (304)≤ 0.08%≤ 2.00%≤ 0.045%≤ 0.030%17.5–19.5% Cr | 8.0–10.5% Ni
Stainless A4 (316)≤ 0.08%≤ 2.00%≤ 0.045%≤ 0.030%16.5–18.5% Cr | 10.0–13.0% Ni | 2.0–2.5% Mo
Brass≤ 0.01%60–63% Cu | Balance Zn

ISO 1580 / DIN 85 Dimensions

Standard metric dimensions in millimetres (mm) according to ISO 1580 specification.

Metric Slotted Pan Head Dimensions

Nominal Size (d) Thread Pitch (P) Head Diam. dk (max) Head Height k (max) Slot Width n (nom) Slot Depth t (min)
M20.40 mm4.00 mm1.30 mm0.50 mm0.60 mm
M2.50.45 mm5.00 mm1.50 mm0.60 mm0.70 mm
M30.50 mm6.00 mm1.80 mm0.80 mm0.85 mm
M40.70 mm8.00 mm2.40 mm1.20 mm1.10 mm
M50.80 mm10.00 mm3.00 mm1.20 mm1.30 mm
M61.00 mm12.00 mm3.60 mm1.60 mm1.60 mm
M81.25 mm16.00 mm4.80 mm2.00 mm2.10 mm
M101.50 mm20.00 mm6.00 mm2.50 mm2.60 mm
Standardization Note: DIN 85 was officially replaced by ISO 1580. Head diameters for M3, M5, and M6 remain identical between both standards, ensuring 100% mechanical interchangeability in standard production.

Where & How to Use ISO 1580 Screws

Electrical & Control Panels

Widely specified for mounting circuit boards, grounding terminals, switchgear, and electrical duct covers in industrial panels across UAE.

Electronics & Instrumentation

Ideal for precision measuring equipment, medical devices, and laboratory enclosures requiring reliable light-duty screw fastening.

HVAC & Ductwork Assemblies

Used to fix access doors, damper controls, and thin sheet metal casings in mechanical building services (MEP).

Corrosive Marine Environments

Stainless steel A4-70 ISO 1580 screws are essential for coastal and marine electrical junction boxes to prevent rust staining.

Easy Field Serviceability

Slotted drives allow simple maintenance and field repair using basic flat-head hand tools without needing specialized driver bits.

Complete RFQ Format

"ISO 1580 Slotted Pan Head Machine Screw, M5 x 20mm, Stainless Steel A2-70, Passivated, Full Thread."

Complementary Fastener Standards

Standard Description Relationship to ISO 1580
DIN 85Slotted pan head machine screwsWithdrawn German equivalent standard to ISO 1580
ISO 7045 / DIN 7985Pan head screws with cross recess (Phillips/Pozidriv)Cross-recess drive variant with identical head profile
ISO 1207 / DIN 84Slotted cheese head machine screwsCylindrical head alternative for deep counterbore holes
ISO 2009 / DIN 965Slotted countersunk flat head screwsFlush-mounting 90° countersunk variant
ISO 1580 FinePan head machine screws with fine pitch threadFine thread metric variant for precision tuning
DIN 934 / ISO 4032Hexagon nutsStandard mating nut for through-hole assemblies
DIN 125 / ISO 7089Plain washersRecommended washer under screw head or nut

Frequently Asked Questions

Is ISO 1580 interchangeable with DIN 85?
Yes. ISO 1580 was developed directly from DIN 85. Head dimensions, slot widths, and thread pitches match across all standard metric sizes, making them interchangeable in commercial applications.
When should I choose ISO 1580 (Slotted) over ISO 7045 (Cross Recess)?
Choose ISO 1580 slotted screws when assemblies need manual field servicing where technicians may only have basic flat screwdrivers, or for aesthetic historical equipment. Choose ISO 7045 (Phillips/Pozi) for automated production lines requiring power drivers.
What material is best for electrical terminal connections?
Brass or Nickel-Plated Brass ISO 1580 screws are best for electrical terminal blocks due to their high electrical conductivity and anti-galling properties. Stainless steel A2 or A4 is preferred for non-conductive, outdoor enclosure covers.
Are ISO 1580 machine screws fully threaded?
Yes. Machine screws under ISO 1580 are standardly manufactured with threads extending fully to the underside of the head for maximum engagement in tapped holes and thin sheet applications.

Need ISO 1580 / DIN 85 Screws in UAE & GCC?

We supply ISO 1580 and DIN 85 slotted pan head machine screws in Steel (4.8, 8.8), Stainless Steel (A2-70, A4-70/80), and Brass. Full stock range from M1.6 to M10 with zinc-plated, nickel-plated, or passivated finishes. Rapid dispatch from RAK FREEZONE.

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