
Product Description
DIN 440-R round flat washer, 9 x 28 x 3 mm, Article number 440RA4090. Made in stainless steel a4. Round Flat Washer manufactured to DIN 440-R. Standard parts to the same standard, property class, dimensions and surface finish are interchangeable between manufacturers; confirm the controlling standard revision, any class-society or application approval, and the mating thread before substitution. Applications: load distribution and locking under bolt heads and nuts in machine building, structural steel, plant maintenance and marine outfitting.
Technical Specifications
- Standard
- DIN 440-R
- Standard description
- R
- Property class / grade
- A4
- Class (detailed)
- A4
- Material hardness
- HV100
- Surface treatment
- Plain (no plating)
- Surface treatment code
- PLAIN
- Diameter
- 8 mm
- Inner diameter
- 9 mm
- Outer diameter
- 28 mm
- Thickness
- 3 mm
- Article number
- 440RA4090
- Category
- Washers / Plain Washers
Standards & Compliance
- Standard
- DIN 440-R
- Size / Series
- 9 x 28 x 3 mm
- Material
- Stainless A4
- HS Code
- 731822
Product Documentation
More from Bufab

Bufab
DIN 440-R Round Flat Washer, Stainless A4, 17.5 x 56 x 5 mm (440RA4180)

Bufab
DIN 440-V Round Flat Washer with Square Hole, Steel, 11 x 34 x 3 mm, Zinc Plated
440V1101

Bufab
DIN 6319-C Spherical Washer, Steel, 6.4 mm, Plain
6319C06

Bufab
DIN 6319-C Spherical Washer, Steel, 6.4 mm, Zinc Plated
6319C061

Bufab
DIN 6319-C Spherical Washer, Steel, 8.4 mm, Plain
6319C08

Bufab
DIN 6319-C Spherical Washer, Steel, 10.5 mm, Plain
6319C10

Bufab
DIN 6319-C Spherical Washer, Steel, 13 mm, Plain (6319C12)

Bufab
DIN 6319-C Spherical Washer, Steel, 13 mm, Plain (6319C13)
Technical guides
Catalogue entry last verified: 2026-09-30. A manufacturer datasheet is attached to this entry — confirm application-critical values against it.
Frequently asked questions
- Where can I buy 440RA4090?
- 440RA4090 can be ordered from cballast.com as a Bufab catalogue item: request a quotation on this page or email sales@cballast.com, and the order ships worldwide.
- What is the manufacturer part number for this Bufab product?
- The manufacturer part number is 440RA4090.
- What is the HS code for 440RA4090?
- The customs tariff (HS) code for 440RA4090 is 731822.
- Who manufactures 440RA4090?
- 440RA4090 is a Bufab product in the C-Parts range.
- Is a datasheet available for 440RA4090?
- Yes — the 440RA4090 datasheet can be viewed and downloaded on this page.
- What is the minimum order quantity for 440RA4090?
- The minimum order quantity is 1.
- Is 440RA4090 available?
- Yes — 440RA4090 is available to order: fulfilment is from supplier stock in cBallast's European network, dispatched directly from the warehouse to the customer, with the exact lead time stated in the quotation (reply within 24 hours).
