From the manual (pg 39): http://www.ilfordphoto.com/Webfiles/...1151751747.pdf

Prints from graded paper such as ILFOSPEED can be made using the ILFOSPEED
MULTIGRADE 500 equipment. ILFOSPEED paper is only sensitive to blue light , therefore
select contrast grade 4 or 4 1/2 (suggested) on the control unit as a compromise between
exposure time and image visibility .