This item is much shorter than a standard Olympic barbell and cannot have weight plates added to it, hence why it is a fixed weight bar. They are coated with a thick foam type material to make them more comfortable to grip/have against your body.
The short of it: these are great for a group workout class/targeted use in a studio, good for a home gym user who has additional capital/a specific use case, but not really useful for most home gym owners.
These are very popular in studios/group fitness spaces because it is the most efficient way to grab a barbell… no loading or unloading of plates required! Just grab the bar and get after it. In turn, this is part of why they are not useful for most home gym owners. It is a very versatile piece of equipment, but requires you to buy a new one each time you get stronger (taking up more space and increasing cost).
If you’re looking for something similar to use in your home gym, it would be best to get an Olympic technique/training bar instead. The base weight of these bars is 15 pounds and it is 5 feet long but it can be loaded with Olympic weight plates, thus giving you the versatility to increase weight as you need without needing to buy more bars (and generally you’ll already have Olympic plates at home that you can use).