These are the rubber booties that cover the cable on your throttle or choke adjusters.
You can either order the short rubber bootie [bottom] that covers cable adjusters on your Dellorto carbs or the longer one [top] that goes over the choke adjuster on PHF carbs etc.
The short one is about an inch long and can be used on throttle cables, choke cables and is also used to protect side stand switches on bevel drives. The long size is about 2 inches long and is primarily used for the choke cable adjuster on PHF/M carbs but can be used in many other applications. Specify which you need.