Abstract: A sterile entry system for use in transferring blood from a unit of blood to a transfer bag wherein the transfer bag is provided with a cannula extending from a disc of predetermined size and the unit of blood includes an access port defining structure and the sterile entry system comprises a sleeve having an open end sized to snugly jacket the exterior periphery of the disc and a closed end, a base spanning the end, and the base having an upper surface within the sleeve and a lower surface exterior of the sleeve and the base including a through bore extending between the surfaces, the through bore having seal means spanning the opposite ends thereof and the seal means being adapted to be pierced.