Don't mistake the instance for the class. The class of categorical imperatives, per Wikipedia: A categorical imperative ... denotes an absolute, unconditional

Don't mistake the instance for the class. The class of categorical imperatives, per Wikipedia: A categorical imperative ... denotes an absolute, unconditional requirement that asserts its authority in all circumstances, both required and justified as an end in itself. Whereas Kant's Categorical Imperative is an instance of that class, specific to morality: Act only according to that maxim whereby you can at the same time will that it should become a universal law.