I took one look at it and thought hummmm "Pro Kennex made OEM stick". They made tons of them.He-he, I was joking...
But it does look like something that Pro Kennex might have made; they used to make frames for many brands.
I did a search in Chinese and, lo and behold, there are other Mastiff racquets out there, albeit badminton ones:
So I'm sticking to my guess that it is a Pro Kennex made OEM stick. But no solid info to lean on, just a guess
Edit: did another search and it seems now the Mastiff badminton racquets are made/sold? by a Chinese brand called The 3rd Game. But your racquet seems much older so I still stay with the original guess.