The present invention may be deployed in a system comprising a security module housed on a chip card and a host device comprising a chip card reader. The host device is comprised in a housing with a slot for the chip card. The housing is shielded to reduce the amount of electromagnetic radiation generated by the security module and/or the host device from penetrating to the exterior of the housing. Similarly, the shielding is adapted to reduce the effects of electromagnetic radiation generated outside of the host device on the components within the housing. The slot is also shielded by a flap made of an electrically conductive epoxy material or an electrically conductive resin.