Apparatus to connect a medication reservoir to a pump housing, comprises a cap (4) connected to the medication reservoir to be secured into the pump housing, a tab (44) formed on the top of the cap so as to provide a surface for a user to grip and twist the cap to engage the cap, connected to the medication reservoir, with the pump housing a needle located internal to the cap (4) to pierce a septum of the medication reservoir a raised portion of the cap having a cavity to secure to infusion set tubing and an engagement member disposed on the cap to engage a housing engagement member of the pump housing, wherein the cap connected to the medication reservoir forms an integrated unit that is secured into the pump housing when the engagement member disposed on the cap (4) is engaged with the housing engagement member.
