Part number 11.4118.091.82330mm x 8mm
Also includes a free DU bush too
If you need a new Red sag ring for your shock, please see Ebay item number 284184337146
People often over-complicate the measuring of shock mounting hardware. Please see the 3rd image for a really easy visual guide. Remember its your frame that dictates what size mounting hardware you need, not the shock.
If you're still unsure please send a message :-)