This washer sit between the slide and needle circlip clip, giving you 1/2 height in between needle clips. Fits most carbs including Dellorto PHBH, VHSH, VHSB Etc, and Mikuni TMX, TM Etc.
Only suitable for Lambrettas or Vespas with non standard carbs.
You can also buy the circlip, click here:  http://www.lambrettaupgrades.co.uk/apps/ webstore/products/show/4404492
 
Price includes VAT @ 20%