Picture the muffler like a long PVC coupling connector. Each end fits into central vacuum PVC tubing (2 OD), or an exhaust port on a central vacuum (usually 2 OD). So, you can use 90s, 45s, etc. to make the muffler go any direction you want, or be as close or as far from the vacuum as you want. We caution running an exhaust run too long though (over 15ft or so) because it starts to create back pressure (regardless if you use a muffler or not).