An assembly (102) of a drug delivery system (100), comprising: a first component (202, 204, 206, 208, 210); a second component (202, 204, 206, 208, 210) which is configured to move linearly with respect to the first component (202, 204, 206, 208, 210); and, a resistance element configured to resist linear movement during transport of the first component (202, 204, 206, 208, 210) with respect to the second component (202, 204, 206, 208, 210) in a closed transport configuration but which is adapted to be overcome during nominal operation of the drug delivery system (100).