A tray according to the present invention comprises a plastic body having upper and lower surfaces. A number of bottom sockets are distributively formed in the upper surface of the body so the respective bottom portions of bottles can be inserted individually in the bottom sockets. Each bottom socket has a configuration which is obtained by connecting those portions of the respective cross-sectional contours of the bottom portions of two or more different types of bottles which are situated outermost when the individual contours are superposed concentrically so that at least two diametrically facing regions of the one contour are not situated inside the other contour. Cap socket corresponding one of the bottom sockets is defined on the lower surface of the body. Each cap socket is a hole, such as a stepped hole, which has at least two hole portions with different inside diameters.