Why is the model not displayed in user_permissions?

Question

Django

Hello.
The essence is this: there are 2 models (product, category). In each of them there is an M2M field to each other through (through='ProductCategory').
So, when I log in as admin, the ProductCategory model is visible in the admin panel.
But, this model is not in the changes of rights for groups (not in the list of Available rights).
Who will tell you what the jamb is?
Thank you in advance

Answer 1

And why do M2M fields in both models?)
Wouldn't it be enough to specify only in Category
products_list = models.ManyToManyField(Product)