Select the host enter key used when the Mouse Wheel is moved to scroll UP when the Mouse Wheel is active using Mouse Wheel Sends PageUp or PageDown Keys.
Default is PageUp -- for 3270 hosts it is usually a PF key like PF7.
In a Profile, this value can be inherited from a linked, parent profile. The Track Marks () will indicate if the value is default, from the parent Profile or unique to this profile.