I bought these new flew on a DA 120 for about 20 flights. Perfect inside not clogged up 100% guaranteed. No restrictions at my field went back to mufflers. I also have three different headers if you want headers they will come with couplers and clamps and a roll of ptfe super extra good the recommended tape to wrap the headers.
DA 90mm drop shown with the headers $140 new, used with extras $115.00
The DA short headers sell for $110.00
The DL111 rectangle port headers $5

Sale pending payment