Immunoglobulin libraries are provided that contain randomly assembled FR1, CDR1, FR2, CDR2, FR3, CDR3 and FR4 sequences of heavy or light chain immunoglobulin variable regions. The backlight module comprises a backplane, a PCB and locking pieces for fixing the PCB on the backplane; the backplane comprises a frame formed by multiple brackets, and bridges arranged on the brackets. An opening having a contour is provided in the deck forwardly of the watercraft’s steering handles.