An infusion set comprising: a base having upper and lower sides (92, 118), a base cannula extending downwardly from the lower side, a rim, and a port extending upward from the upper side, the port being in fluid communication with the base cannula, and the port comprising a septum (130 adapted to seal side port from fluid communication therethrough; an adhesive layer mounted to the lower side of the base; an introducer cap adapted to be pressed against the upper side of the base and removably attached to the base, the introducer cap comprising upper and lower sides, and a needle extending downwardly from the lower side, the needle being adapted to extend through the septum on upper side of the base and through the base cannula on the lower side of the base; and an infusion cap comprising an upper side and a lower side, a port-engaging portion with a tubular wall, and barbed feet adapted to engage the rim of the base, the infusion cap being removably attachable to the base, the port-engaging portion with its tubular wall, closely surrounding the port when the infusion cap Is attached to the base, the infusion cap being adapted to rotate with respect to the base while engaged, the infusion cap comprising an infusion cannula extending downwardly from the lower side of the infusion cap, and an elongate flexible lumen in fluid communication with the infusion cannula, the infusion cannula being adapted to extend through the septum on the upper side of the base upon engagement of the infusion cap and the base to place the flexible lumen and the infusion cap in fluid communication with the base cannula, the tubular wall of the port-engagement portion surrounding and covering the end of the infusion cannula with a vertical dimension (e) between an outlet of the infusion cannula and a bottom edge of the tubular wall of the port-engagement portion and a vertical distance (h) between a top edge of the barbed feet and the bottom edge of the tubular wall of the port-engaging portion. a base having upper and lower sides (92, 118), a base cannula extending downwardly from the lower side, a rim, and a port extending upward from the upper side, the port being in fluid communication with the base cannula, and the port comprising a septum (130 adapted to seal side port from fluid communication therethrough; an adhesive layer mounted to the lower side of the base; an introducer cap adapted to be pressed against the upper side of the base and removably attached to the base, the introducer cap comprising upper and lower sides, and a needle extending downwardly from the lower side, the needle being adapted to extend through the septum on upper side of the base and through the base cannula on the lower side of the base; and an infusion cap comprising an upper side and a lower side, a port-engaging portion with a tubular wall, and barbed feet adapted to engage the rim of the base, the infusion cap being removably attachable to the base, the port-engaging portion with its tubular wall, closely surrounding the port when the infusion cap Is attached to the base, the infusion cap being adapted to rotate with respect to the base while engaged, the infusion cap comprising an infusion cannula extending downwardly from the lower side of the infusion cap, and an elongate flexible lumen in fluid communication with the infusion cannula, the infusion cannula being adapted to extend through the septum on the upper side of the base upon engagement of the infusion cap and the base to place the flexible lumen and the infusion cap in fluid communication with the base cannula, the tubular wall of the port-engagement portion surrounding and covering the end of the infusion cannula with a vertical dimension (e) between an outlet of the infusion cannula and a bottom edge of the tubular wall of the port-engagement portion and a vertical distance (h) between a top edge of the barbed feet and the bottom edge of the tubular wall of the port-engaging portion.