When you add multiple instances of the same component to an assembly, the software automatically numbers each instance in ascending order. The instance number <n> appears next to the component name in the FeatureManager design tree.
When you delete a component instance, other instances of the same component do not change instance numbers. For example, Seat Assembly contains Bracket<1>, Bracket<2>, Bracket<3>, and Bracket<4>. If you delete Bracket<2>, the assembly now contains Bracket<1>, Bracket<3>, and Bracket<4>.
When you save a component instance as a new part by right-clicking and clicking Make Independent, the instance number of the newly created component is <1>.
When you replace a component with a component that does not already exist in the assembly, the instance number changes to <1>. However, if the replaced component already exists in the assembly, the instance number changes to n +1, where n is the highest instance number already in the assembly.