Are collars and EPP augmentations permanent?

Both EPP augmentations and collars are items that can be attached to existing items. I would like to know if the attachment process is permanent, and if it is not, then do we get the previous item back once we attach a new item?

EPP augmentations are lost when you upgrade your EPP (e.g: from radiation to heating). Once you have applied an augmentation, there is no way to get it back as an item; applying a new augmentation will overwrite it. The augmentation will stay on the EPP until you either upgrade the EPP or apply a new augmentation.

Pet collars work similarly, in that they will stay on the pet until you apply a new one to overwrite it, with the difference that pets cannot be upgraded.

Sources: Here, here, and personal experience.