What is the SKF MB 4 lock washer used for?

It is used to secure KM 4 lock nuts on a shaft or adapter sleeve to prevent unintentional loosening.

What are the dimensions of this lock washer?

The washer has an inside diameter of 20 mm and an outside diameter of 36 mm.

How does this lock washer secure the nut?

The inner tab engages the shaft keyway and one outer tab bends into a slot on the lock nut.

Can a used lock washer be reused?

No, a new lock washer should be used each time the lock nut is installed for reliable locking.

Which lock nuts are compatible with the MB 4?

This lock washer is compatible with KM 4 lock nuts.

SKF MB 4 lock washer for lock nuts 20 x 36 mm

Supplier number: SKF MB 4 | EAN 7316570803693

1.34 tax incl.

€1.11 excl. VAT (incl. all environmental contributions)

On stock - immediately available

Ordered before 20:00 - delivered tomorrow 09/10/2026
Shipping costs €11.99 VAT included | Free shipping for orders over a total amount of 125 euros
Delivery by DHL

↓ Documents (1) ✆ Talk to a specialist

Reliable shaft locking with Skf MB 4

Practical benefits

Prevents accidental loosening: The robust outer tabs fold smoothly into the nut slot so you keep bearing assemblies firmly in place.
Accurate keyway engagement: The internal tab aligns directly with your shaft keyway to provide you with secure anti-rotation support.
Fast and simple installation: You easily bend the locking tab with standard tools to complete a dependable mechanical lock in seconds.

In a nutshell

The right choise for

With the Skf mb 4 lock washer, you reliably secure km 4 lock nuts on shafts and adapter sleeves. Featuring an inside diameter of 20 mm and an outside diameter of 36 mm, its internal tab engages directly into the shaft keyway to prevent rotation. By simply bending one of the outer tabs into a slot on the lock nut, you protect assemblies from loosening under continuous vibration and dynamic loads, keeping bearing positioning and preload consistently accurate.

Product information FAQ

€1.34

In stock - tax incl.

Key features according to our expert

Inner diameter: 20 mm
Outer diameter: 36 mm

Product description

MB and MBL lock washers are locking devices, used to secure KM, KML and HM .. T lock nuts onto a shaft or adapter sleeve and prevent unintentional loosening. MB .. A is a stronger version of the MB washer. The lock washers engage a keyway in the shaft or adapter sleeve thread. They lock the nut in position when one of the washer tabs is bent into one of the slots in the outside diameter of the lock nut. A new lock washer should be used each time the corresponding lock nut is installed.

Simple, stable and reliable fastening element
Easy to install and remove
Used for KM, KML, and HM .. T lock nuts

Documents

⤓ Technical data sheet PDF

All Features

Inner diameter: 20 mm
Outer diameter: 36 mm
Outer diameter: 36
Bore diameter: 20
Locking device: Lock washer

Brand SKF
01230629
EAN 7316570803693
Supplier number SKF MB 4

Frequently asked questions about this product

Answered by specialists

What is the SKF MB 4 lock washer used for?: It is used to secure KM 4 lock nuts on a shaft or adapter sleeve to prevent unintentional loosening.
What are the dimensions of this lock washer?: The washer has an inside diameter of 20 mm and an outside diameter of 36 mm.
How does this lock washer secure the nut?: The inner tab engages the shaft keyway and one outer tab bends into a slot on the lock nut.
Can a used lock washer be reused?: No, a new lock washer should be used each time the lock nut is installed for reliable locking.
Which lock nuts are compatible with the MB 4?: This lock washer is compatible with KM 4 lock nuts.