A device for examining/treating an eye has a base body and an attachment body, which can be combined and applied to the eye. A gel-type liquid is introduced between the two bodies so that the indices can be matched. The interior of the attachment body is provided with a large number of protuberances, ensuring a minimum distance is maintained between the two bodies, allowing air or excess liquid to escape between the two bodies to escape. Only the attachment body, a disposable item producible from cheap materials, needs to be sterilized and a single sterilization is integrated into the production process. The base only needs to be disinfected. This division of the device also allows a large number of base bodies with different configurations to be used with one single attachment body or a large number of attachment bodies with different configurations to be used with one single base body.