The invention relates to a window unit (10) comprising a window pane (11) and a frame (12). The frame (12) consists of two parts, a basic frame (15) and an additional frame (16). The basic frame (15) has a bearing surface (17) which contacts the window pane (11) to which the frame is permanently fixed by means of an adhesive layer (19) deposited on the bearing surface. The basic frame (15) further comprises a connecting surface (21) for the additional frame (16). Said additional frame (16) in turn also has a connecting surface (21) of the basic frame (15). The two frame parts (15; 16) are removably or permanently joined together via their connecting surfaces (21; 26).