This is a rear subframe from a 1997 CBR 1100 xx blackbird

This has some holes drilled in it 

has some grind marks on it 

and this is probably the cheapest one that a guy would want to use when you're out to modify your bike and make changes to it but don't want to hack up a good rear subframe

So it's inexpensive and comes with the fasteners to the frame as shown