Scirocco Register

I've removed the rear shock absorbers from my GTX & stripped them down. The old ones (Cofap) have a small circlip on the piston rod (Haynes manual shows one too). But my new shocks don't have a circlip & don't have a groove where the circlip could fit either. What's the circlip for? Is it required?

Cheers

If i remember correctly, the clip is there to stop the bump stop slipping down.