DIN 125 B
Plain Washers, Type B
Manufacturer Mumbai
What Is a DIN 125 B Chamfered Plain Washer
DIN 125 covers close-tolerance flat washers in two variants: Type A is the plain version, with a square inner edge; Type B adds a small chamfer around that inner edge. The reason for the chamfer comes down to bolt head geometry. Many bolts, especially higher property class fasteners, are manufactured with a fillet radius where the underside of the head blends into the shank — a deliberate stress-relief feature that improves the bolt’s fatigue performance.
A square-edged washer sitting against that fillet doesn’t seat flat — it rocks on the radius, or the fillet prevents full contact around the bore, reducing the effective bearing area exactly where full contact matters most. The chamfer on a Type B washer is machined to clear that fillet, letting the washer’s flat face make complete, even contact with the bearing surface while the bolt head or nut still seats correctly against the washer’s top face. It’s a small dimensional detail, but it’s the difference between a washer that seats properly under a high-tensile bolt and one that doesn’t.
Akbar Fasteners Pvt. Ltd. manufactures DIN 125 B plain washers in-house at our Mumbai facility, under ISO 9001:2015, with full mill test documentation, and exports this range to over 50 countries.
Where DIN 125 B Washers Genuinely Earn Their Place
Clears the Bolt Head Fillet
The chamfered inner edge is specifically machined to clear the fillet radius under high property class bolt heads and nuts.
Full, Flat Bearing Contact
Seats fully and squarely against the bearing surface instead of rocking on the fillet radius of the fastener.
Full Size & Weight Reference
A published dimension and weight chart lets you plan quantity and freight before an order is placed, not after.
Wide Material & Finish Choice
Carbon steel and stainless steel available across the full size range, in bulk quantities for structural and OEM assembly needs.
DIN 125 B Plain Washer Dimension & Weight Chart
Standard nominal dimensions and approximate weight by bolt size — inner diameter (d1) matches the close-tolerance DIN 125 series, with the chamfer as the distinguishing Type B feature sized to your bolt’s fillet radius. Weight is given per 100 pieces; actual weight may vary slightly with material and finish selected.
| Bolt Size (d) | Inner Dia. (d1) | Outer Dia. (d2) | Thickness (s) | Chamfer | Approx Weight/100pcs |
|---|---|---|---|---|---|
| M4 | 4.3 mm | 9.0 mm | 0.8 mm | 0.3 mm | ~0.22 kg |
| M6 | 6.4 mm | 12.0 mm | 1.6 mm | 0.4 mm | ~0.60 kg |
| M8 | 8.4 mm | 16.0 mm | 1.6 mm | 0.5 mm | ~1.10 kg |
| M10 | 10.5 mm | 20.0 mm | 2.0 mm | 0.5 mm | ~1.95 kg |
| M12 | 13.0 mm | 24.0 mm | 2.5 mm | 0.6 mm | ~3.05 kg |
| M16 | 17.0 mm | 30.0 mm | 3.0 mm | 0.8 mm | ~4.85 kg |
| M20 | 21.0 mm | 37.0 mm | 3.0 mm | 0.8 mm | ~7.20 kg |
| M24 | 25.0 mm | 44.0 mm | 4.0 mm | 1.0 mm | ~11.60 kg |
| M30 | 31.0 mm | 56.0 mm | 4.0 mm | 1.0 mm | ~18.70 kg |
Figures shown are representative reference values in steel for quick planning purposes and may vary slightly by manufacturer tolerance and material selected. Please confirm exact dimensions against the current DIN 125 standard document or your engineering drawing, and request our certified dimensional data sheet, before finalizing a purchase order.
Flat Washer Product Range
Plain Washers, Chamfered Type B
Close-tolerance washers with chamfered inner edge for high-tensile bolt fillet clearance, M3 to M64.
DIN 125 APlain Washers, Standard Type A
Square-edged counterpart to Type B, for standard property class bolts without a significant fillet.
DIN 126Plain Washers, Wide Clearance
Wider inner diameter flat washers for structural and coarse-hole bolting applications.
DIN 127 BSpring Lock Washers
Helical split lock washers for anti-loosening spring tension and mechanical bite.
DIN 125 B Technical Overview
Available Materials
- Carbon Steel Standard Offering
- Stainless Steel A2 / A4 on Request
- Alloy Steel High-Load Applications
- Surface Finish Zinc Plated / Black Oxide
- Custom Material To Specification
Chamfer & Tolerance Details
- Inner Edge Chamfered, Type B
- Hole Tolerance Close, per DIN 125
- Product Grade Grade A Typical
- Flatness Standard Manufacturing Tolerance
- Testing MTC / NABL on Request
Available Dimensions
- Bolt Size M3 – M64
- Custom Sizes To Drawing on Request
- Standard Reference DIN 125 B
- Thickness Range 0.8 – 6.0 mm
- Packaging Loose / Boxed / Bulk
Application Areas
Wherever a high property class bolt’s fillet radius needs proper washer clearance.
High-Tensile Structural Bolting
connection assemblies
Automotive & Chassis Assembly
higher-grade bolts
Machine Tool Assembly
requiring full bearing contact
Pressure Vessel Flanging
gasketed flange joints
Wind Turbine & Tower Assembly
structural connections
Aerospace Ground Equipment
with high-grade fasteners
Power Generation Equipment
rotating and static equipment
General Precision Assembly
volume manufacturing
Standard Export Documentation
Prepared as standard practice for every plain washer shipment.
Mill Test Certificate (MTC)
Material composition and mechanical property verification for every production batch.
Certificate of Conformance
Confirms the shipment matches the purchase order specification, size, and type in full.
Certificate of Origin (COO)
Confirms India as country of manufacture for destination customs purposes.
Commercial Invoice & Packing List
Itemized value, Incoterm, and detailed carton/weight breakdown for customs clearance.
Dimensional Data Sheet
Certified inner/outer diameter and chamfer dimension data against DIN 125 B available on request before order confirmation.
Bill of Lading
Ocean or air freight shipping document confirming carrier, mode, and consignee details.
Internationally Recognised Standards Coverage
Related Fastener Grades & Standards
DIN 126 Plain Washers
Wider inner diameter flat washers for structural and coarse-hole bolting applications.
View DIN 126 →DIN 127 B Spring Lock Washers
Helical split lock washers offering spring tension plus sharp-edge bite for vibration resistance.
View DIN 127 B →DIN 93 Tab Washers
Bendable locking washers offering a physical, verifiable safety locking mechanism.
View DIN 93 →Top Nickel Fasteners Manufacturer
See our full in-house nickel alloy manufacturing and documentation capability.
View Manufacturer Page →Send Us Your
Bolt Grade & Quantity
Tell us your bolt size, property class, and quantity — we’ll confirm the correct DIN 125 B specification and issue a certified dimensional data sheet with your quote. Akbar Fasteners Pvt. Ltd. responds within 24 hours.
Sales: +91 724 0000 733 · Support: +91 800 9315 333 · sales@akbarfasteners.in