网上查了下这个问题很普遍，然后他们自己做：You can go to a 4" pvc sch 40.
demons(堂·吉诃德)
Take some stainless steel screen and wrap it in a 2" tube. Wrap it with more screen until it fits snug in the 4". Glue the other 2" reducer on it. Make it as long as possible. Should be an instant glasspack.
(#11121977@0) Last Updated: 2017-10-18 This post has been archived. It cannot be replied.