Lock washer name??

[johno]

There is a type of lock washer, that is in two parts.
One side of each is serrated, these sides ride againest each other.
So for the bolt/nut to loosen it effectively has to tighten first to ride over the serations.
Theoretically.
I cannot remember the name of these, can someone help?

Thanks

 

[Avgas]

serrated lock washer?

 

[johno]

Hah found it, Nord- lock.


http://www.nordlock.com/default.asp?url=2.16.37

 

[Outlawmws]

Disc lock washer?

http://www.ondrives.com/fasteners-washers-to-suit-m5-m12.html

 

[johno]

Disc lock washer?

http://www.ondrives.com/fasteners-washers-to-suit-m5-m12.html

Thats them.

Thanks