A cap assembly for a drug delivery device is described that includes a cap housing defining an internal cavity and a remover configured to be insertably mounted within the internal cavity of the cap housing and having a sidewall with a generally annular configuration. A plurality of retention portions of the remover extend radially inwardly from the sidewall within the internal cavity, such that the plurality of retention portions are configured to grip a needle shield inserted through the remover within the internal cavity of the cap housing. A drug delivery device is also described that includes a cap assembly kit including a cap housing having an internal cavity sized to interchangeably receive one of a first remover or a second remover, where the first remover is configured to receive a first type of needle shield and the second remover is configured to receive a second type of needle shield.