I have spoken to many people in my FB groups and forums. It seems as the the coupler(s) that come with the catted DP do not fit snugly and leak. I have personally tried to adjust it several times with no luck. To be clear, it is the DP to Coupler not the coupler to exhaust. That end fits snugly with no leaks.Hey folks - since the thread is active just a head's up that our best sale of the year is active! 10% off plus no taxes added (we eat the cost) and free shipping to the lower 48 on any CVF-branded products. Feel free to give me a shout via PM if you have any questions as well!