A valve for use in irrigating, accessing and sealing the instrument channel of an endoscope is disclosed. The valve is adapted for installation onto an endoscope instrument inlet port. The valve includes an outer shell and a plurality of disks. The outer shell has a proximal end adapted for insertion of an instrument, interior walls defining a cavity, and a distal end adapted for connection to the instrument inlet port. The plurality of disks are disposed within the cavity in a stacked orientation. Each disks has an aperture therethrough for insertion of an instrument. The plurality of disks cooperate to maintain a seal around an instrument inserted through the valve.
