>>2920331Notice the sharp corner in pic related.
Notice how there's no small hook on the end of the tool you posted.
Yes, you have posted a paint roller. A roller brush will slide on the end and be retained between the corner of the bar and the slightly crimped very end of the bar.
OP's pic does not have a sharp corner that will keep the brush in place, but a rather gradual curve, which a brush would ride up on and bind.
Second, the small hook on the end of OP's tool would interfere with any brush you happen to put on there and the thing would simply not roll very well at all.