A clamshell housing includes a first housing part defining having a first interface edge and a first rib that protrudes from the first interface edge, and a second housing part having a second interface edge and a second rib that protrudes from the second interface edge. An elastomeric gasket is interposed between the first interface edge and the second interface edge. The gasket has a first groove configured to receive the first rib and a second groove configured to receive the second rib. The first rib is configured to form a seal with the first groove, and the second rib is configured to form a seal with the second groove.