An exhaust treatment system includes first and second exhaust conduits positioned on opposite ends of an exhaust treatment device. The exhaust treatment device includes a housing having a first outer diameter at a first end and a different second outer diameter at a second end. A clamp includes an inner surface engaging both the first exhaust conduit and the exhaust treatment device when the exhaust treatment device is positioned with its first end adjacent to the first exhaust conduit. The inner surface of the clamp is spaced apart from one of the housing and the exhaust treatment device when the second end of the exhaust treatment device is adjacent the first exhaust conduit.