ISO 7089Flat washer

ISO 7089 M5 Flat washer

ISO 7089 M5 is a flat washer, sized for M5 bolts. The general purpose flat washer. It protects the clamped surface, bridges oversized holes and spreads load under the head or nut.

Dimensioned drawing — ISO 7089 M5d2 10⌀5.3h 1
ISO 7089 M5 — Flat washerNominal dimensions in mm · Not to scale
ThreadM5
Inside Ø d15.3 mm
Outside Ø d210 mm
Thickness h1 mm

Dimensions

Standard
ISO 7089
Type
Flat washer
Size
M5
For bolt size
M5
Total height h
1 mm
Inside diameter d1
5.3 mm
Outside diameter d2
10 mm

Nominal values in millimetres as published in ISO 7089. Estimated weight 0.443 g per piece in steel (0.446 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.

Other lengthsISO 7089 M5

All M5 specifications

Interchangeability

ISO 7089 is catalogued with DIN 125 A as its equivalent designation. Dimensions are compared field by field rather than assumed identical.

Choosing and fitting this size

ISO 7089 M5 is a washer with a 5.3 mm inside diameter. It sits under a bolt head or nut to spread the clamping load; the inside diameter matches the bolt it is specified for, so the washer and fastener should always be ordered as a pair.

Hardness is the governing property rather than tensile strength: a 200 HV washer suits bolts up to class 10.9, while 140 HV washers are intended for class 8.8 and below. Using a soft washer under a high-grade bolt lets the washer deform before the bolt reaches its preload, which quietly loses clamping force.