Abstract: A closure cap for protecting a capillary tube incorporates a hollow body member is dimensioned to fit within a container. The container and closure cap are used in shipping micropipets in a impact absorbing, sterile environment. An elongated tube retaining portion is centrally positioned within the hollow body member and extends at least a substantial portion of the length of the body. The tube retaining portion has a centrally disposed channel with at least one open end for receiving and retaining a tube in a friction fit. The air tight seal allows for sterility. A plurality of radially extending, equally spaced, retaining webs connect the tube retaining portion and the body along at least a major portion of the length of the tube retaining portion. The closure cap is air impermeable, flexible and formed of an inert material which is heat and radiation resistant.