@startuml
left to right direction

hide circle
package relations {

  note right of WinterWheel
     The winter wheels are 
     only attached during winter. 
    They are stored away in summer. 
  end note

  Car "1" -- "4" WinterWheel: knows 

  note right of SpareWheel
     The spare wheel might replace an
     attached wheel in case of emergency.
  end note

  Car "1" --o "1" SpareWheel: has

  note right of MainWheel
     The main wheels are 
     permanently attached.
   end note

  Car "1" --* "4" MainWheel: consistsOf
}




@enduml