# '''[[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Active_Lumped_Two-Port_Device | Active Lumped Two-Port Device]]'''
Although lumped devices are not sources and do not excite a structure, their properties are similar to lumped sources. A lumped device has to be associated with a PEC line object that is parallel to one of the three principal axes. Similar to lumped sourcesources, lumped devices have a an '''Offset''' parameter that is equal to the distance between their location on the host line and its start point.
A lumped device is characterized by a v-i equation of the form: