in greater detail below passageway 34 operates as a conduit directing the output energy from one pyrotechnic device located adjacent forward sections 16 and 30 toward the second pyrotechnic device located adjacent aft sections 18 and 32 the forward section 30 of device insert 14 comprises a circumscribing channel 36 that is configured to receive an o ring 38 o ring 38 provides a seal between insert 14 and housing 12 and also assists in maintaining insert 14 within bore 22 upon assembly of device 10 forward section 30 of insert 14 generally is of greater diameter than aft section 32 thus corresponding with the general configuration of bore 22 the junction between forward section 30 and aft section 32 comprises a shoulder 40 that abuts a similarly configured shoulder 42 defining the junction between forward section 16 and aft section 18 of housing 12 the contacting engagement of both shoulders 40 42 ensures proper mating of insert 14 and housing 12 in certain embodiments housing 12 and insert 14 can be manufactured from a variety of metals including stainless steel although different stainless steel alloys may be selected individually for each piece in one particular embodiment housing 12 may comprise 17 4.